chemistry problem solving a step by step

• PRO Courses Guides New Tech Help Pro Expert Videos About wikiHow Pro Upgrade Sign In
• EDIT Edit this Article
• EXPLORE Tech Help Pro About Us Random Article Quizzes Request a New Article Community Dashboard This Or That Game Popular Categories Arts and Entertainment Artwork Books Movies Computers and Electronics Computers Phone Skills Technology Hacks Health Men's Health Mental Health Women's Health Relationships Dating Love Relationship Issues Hobbies and Crafts Crafts Drawing Games Education & Communication Communication Skills Personal Development Studying Personal Care and Style Fashion Hair Care Personal Hygiene Youth Personal Care School Stuff Dating All Categories Arts and Entertainment Finance and Business Home and Garden Relationship Quizzes Cars & Other Vehicles Food and Entertaining Personal Care and Style Sports and Fitness Computers and Electronics Health Pets and Animals Travel Education & Communication Hobbies and Crafts Philosophy and Religion Work World Family Life Holidays and Traditions Relationships Youth
• Browse Articles
• Learn Something New
• Quizzes Hot
• This Or That Game New
• Train Your Brain
• Explore More
• Support wikiHow
• About wikiHow
• Log in / Sign up
• Education and Communications

How to Do Stoichiometry

Last Updated: December 2, 2022 Fact Checked

This article was co-authored by Bess Ruff, MA . Bess Ruff is a Geography PhD student at Florida State University. She received her MA in Environmental Science and Management from the University of California, Santa Barbara in 2016. She has conducted survey work for marine spatial planning projects in the Caribbean and provided research support as a graduate fellow for the Sustainable Fisheries Group. There are 13 references cited in this article, which can be found at the bottom of the page. This article has been fact-checked, ensuring the accuracy of any cited facts and confirming the authority of its sources. This article has been viewed 274,639 times.

In a chemical reaction, matter can neither be created nor destroyed according to the law of conservation of mass, so the products that come out of a reaction must equal the reactants that go into a reaction. This means the same amount of each atom that you put in must come back out. Stoichiometry is the measure of the elements within a reaction. [1] X Research source It involves calculations that take into account the masses of reactants and products in a given chemical reaction. Stoichiometry is one half math, one half chemistry, and revolves around the one simple principle above - the principle that matter is never lost or gained during a reaction. The first step in solving any chemistry problem is to balance the equation .

Balancing the Chemical Equation

• Don’t forget to multiply through by a coefficient or subscript if one is present.
• For example, H 2 SO 4 + Fe ---> Fe 2 (SO 4 ) 3 + H 2
• On the reactant (left) side of the equation there are 2 H atoms (H 2 ), 1 S atom, 4 O atoms (O 4 ), and 1 Fe atom.
• On the product (right) side of the equation there are 2H atoms (H 2 ), 3 S atoms (S 3 ), 12 O atoms (O 12 ), and 2 Fe atoms (Fe 2 ).

• For example, the lowest common factor between 2 and 1 is 2 for Fe. Add a 2 in front of the Fe on the left side to balance it.
• The lowest common factor between 3 and 1 is 3 for S. Add a 3 in front of H 2 SO 4 to balance the left and right sides.
• At this stage, our equation looks like this: 3 H 2 SO 4 + 2 Fe ---> Fe 2 (SO 4 ) 3 + H 2

• In our example, we added a 3 in front of H 2 SO 4 and now have 6 hydrogens on the left and only 2 on the right side of the equation. We also have 12 oxygen on the left and 12 oxygen on the right, so it is balanced.
• We can balance hydrogens by adding a 3 in front of H 2 .
• Our final balanced equation is 3 H 2 SO 4 + 2 Fe ---> Fe 2 (SO 4 ) 3 + 3 H 2 .

• Let's check our equation, 3 H 2 SO 4 + 2 Fe ---> Fe 2 (SO 4 ) 3 + 3 H 2 , for balance.
• On the left side of the arrow, there are 6 H, 3 S, 12 O, and 2 Fe.
• On the right side of the arrow, there are 2 Fe, 3 S, 12 O, and 6 H.
• The left and the right sides of the equation match, therefore, it is now balanced.

Converting Between Grams and Moles

• Define the number of atoms of each element in a compound. For example, glucose is C 6 H 12 O 6 , there are 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms.
• Identify the atomic mass in grams per mol (g/mol) of each atom. The atomic masses of each element are usually found underneath the element's symbol on a periodic table, usually as a decimal. The atomic masses of the elements in glucose are: carbon, 12.0107 g/mol; hydrogen, 1.007 g/mol; and oxygen, 15.9994 g/mol.
• Multiply each element's atomic mass by the number of atoms present in the compound. Carbon: 12.0107 x 6 = 72.0642 g/mol; Hydrogen: 1.007 x 12 = 12.084 g/mol; Oxygen: 15.9994 x 6 = 95.9964 g/mol.
• Adding these products together yields the molar mass of the compound. 72.0642 + 12.084 + 95.9964 = 180.1446 g/mol. 180.14 grams is the mass of one mole of glucose.

• For example: How many moles are in 8.2 grams of hydrogen chloride (HCl)?
• The atomic mass of H is 1.007 and Cl is 35.453 making the molar mass of the compound 1.007 + 35.453 = 36.46 g/mol.
• Dividing the number of grams of the substance by the molar mass yields: 8.2 g / (36.46 g/mol) = 0.225 moles of HCl.

• For example, what is the molar ratio of KClO 3 to O 2 in the reaction 2 KClO 3 ---> 2 KCl + 3 O 2 .
• First, check to see the equation is balanced. Never forget this step or your ratios will be wrong. In this case there are equal amounts of each element on both sides of the reaction so it is balanced.
• The ratio of KClO 3 to O 2 is 2/3. It doesn’t matter which number goes on top or on bottom as long as you keep the same compounds on the top and bottom throughout the rest of the problem. [11] X Research source

• For example, given the reaction N 2 + 3 H 2 ---> 2 NH 3 how many moles of NH 3 will be produced given 3.00 grams of N 2 reacting with sufficient H 2 ?
• In this example, sufficient H 2 means that there is enough available and you don’t have to take it into account to solve the problem.
• First, convert grams of N 2 to moles. The atomic mass of nitrogen is 14.0067 g/mol so the molar mass of N 2 is 28.0134 g/mol. Dividing mass by molar mass gives you 3.00 g/28.0134 g/mol = 0.107 mol.
• Set up the ratios given by the question: NH 3 : N 2 = x/0.107 mol.
• Cross multiply this ratio by the molar ratio of NH 3 to N 2 : 2:1. x/0.107 mol = 2/1 = (2 x 0.107) = 1x = 0.214 mol.

• The molar mass of NH 3 is 17.028 g/mol. Therefore 0.214 mol x (17.028 grams/mol) = 3.647 grams of NH 3 .

Converting Between Liters of Gas and Moles

• Generally, a reaction will say that it is given at 1 atm and 273 K or will simply say STP.

• For example, convert 3.2 liters of N 2 gas to moles: 3.2 L/22.414 L/mol = 0.143 moles.

• The equation can be rearranged to solve for moles: n = RT/PV.
• The units of the gas constant are designed to cancel out the units of the other variables.
• For example, determine the number of moles in 2.4 liters of O 2 at 300 K and 1.5 atm. Plugging in the variables yields: n = (0.0821 x 300)/(1.5 x 2) = 24.63/3.6 = 6.842 moles of O 2

Converting Between Liters of Liquid and Moles

• If the density is not given within the problem, you may have to look it up in a reference text or online.

• Identify the volume given. For example, let’s say the problem states that you have 1 liter of H 2 O. To convert to mL simply multiply by 1000. There are 1000 milliliters in a liter of water.

• The density of H 2 O, for instance, is approximately 1.0 g/mL.

• Identify the atomic mass in grams per mol (g/mol) of each atom. The atomic masses of the elements in glucose are: carbon, 12.0107 g/mol; hydrogen, 1.007 g/mol; and oxygen, 15.9994 g/mol.
• Multiply each elements atomic mass by the number of atoms present in the compound. Carbon: 12.0107 x 6 = 72.0642 g/mol; Hydrogen: 1.007 x 12 = 12.084 g/mol; Oxygen: 15.9994 x 6 = 95.9964 g/mol.

Community Q&A

You Might Also Like

• ↑ http://www.chemteam.info/Stoichiometry/What-is-Stoichiometry.html
• ↑ https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:chemical-reactions/x2eef969c74e0d802:stoichiometry/a/stoichiometry
• ↑ https://web.ung.edu/media/chemistry/Chapter4/Chapter4-StoichiometryOfChemicalReactions.pdf
• ↑ http://preparatorychemistry.com/Bishop_molar_mass_conversion_factors_help.htm
• ↑ http://www.chemteam.info/Stoichiometry/Mole-Mass.html
• ↑ http://www.chemteam.info/Stoichiometry/Mass-Mass.html
• ↑ https://www.khanacademy.org/science/chemistry/chemical-reactions-stoichiome/stoichiometry-ideal/a/stoichiometry
• ↑ http://www.chemteam.info/Stoichiometry/Molar-Ratio.html
• ↑ http://www.chemteam.info/Stoichiometry/Mole-Mole.html
• ↑ http://www.engineeringtoolbox.com/stp-standard-ntp-normal-air-d_772.html
• ↑ http://www.thegeoexchange.org/chemistry/stoichiometry/liters-to-moles.html
• ↑ https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Physical_Properties_of_Matter/States_of_Matter/Properties_of_Gases/Gas_Laws/The_Ideal_Gas_Law
• ↑ https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Supplemental_Modules_and_Websites_(Inorganic_Chemistry)/Chemical_Reactions/Stoichiometry_and_Balancing_Reactions

About This Article

To do stoichiometry, start by balancing the chemical equation so that the number of atoms on each side of the equal sign are exactly the same. Next, convert the units of measurement into moles and use the mole ratio to calculate the moles of substance yielded by the chemical reaction. Then, convert moles of wanted substance to the desired units of measurement! For tips on converting different units of measurement into moles, read on! Did this summary help you? Yes No

• Send fan mail to authors

Reader Success Stories

Aug 21, 2017

Did this article help you?

Mar 22, 2018

Randy Orton

May 11, 2016

Arnipalli Sateesh

Jan 4, 2017

John Malone

Apr 13, 2016

Featured Articles

Trending Articles

Watch Articles

• Terms of Use
• Privacy Policy
• Do Not Sell or Share My Info
• Not Selling Info

wikiHow Tech Help Pro:

Develop the tech skills you need for work and life

Examples for

Step-by-Step Chemistry

See how to solve chemistry problems step by step across all levels of the curriculum, from middle school to college. Topical coverage spans analytical, inorganic, organic and physical chemistry and biochemistry subdivisions. Use Wolfram|Alpha to solve and truly understand chemistry at an atomic and molecular level.

Chemical Conversions

Convert chemical quantities to other chemical units.

Follow the steps for unit conversion:

Explore the properties of molecules.

Calculate molecular mass:

Compute the elemental composition of molecules:, count the total number of particles:.

Build chemical kinetic equations step by step.

Construct the reaction rate expression:

Build the rate-of-conversion expression:.

Analyze the properties of chemical solutions.

Compute the molarity of a solution step by step:

Prepare a dilute solution step by step:, compute the boiling point elevation for a solution:, convert between density and concentration for a single-component solution:, titrate a strong acid or base:, prepare chemical solutions step by step:.

Explore the properties of atoms step by step.

Calculate the atomic mass:

Assemble a ground-state orbital diagram:, count the number of valence electrons:, compute the energy of a photon from its wavelength:, find the wavelength of a photon from a co 2 (g) laser:, compute the de broglie wavelength:, build the nuclide symbol:, find the neutron number:.

• Chemical Reactions

Analyze chemical reactions step by step.

Learn how to balance a chemical reaction:

Find the required amount of reactants:, determine the theoretical yield:, compute the percent yield:, compute total ionic equations:, determine net ionic equations:, find the spectator ions:, structure & bonding.

Investigate the structure and bonding properties of individual molecules.

Get a step-by-step procedure to draw the Lewis structures of molecules:

Compute oxidation states of chemicals:, determine orbital hybridization one step at a time:, use hückel's rule to determine aromaticity:, thermodynamics.

Investigate the thermochemical properties of compounds step by step.

Compute the change in internal energy:

Compute the heat capacity ratio:, related examples.

• Chemical Quantities
• Cheminformatics

Equilibrium

Construct the steps to solve chemical equilibrium equations for chemical reactions.

Learn to build an equilibrium constant:

Assemble a reaction quotient:.

Compute the properties of chemicals in the gas phase step by step.

Calculate molar properties for gases:

Determine the amount of a gas:, find the volume of a gas:.

Please ensure that your password is at least 8 characters and contains each of the following:

• a special character: @$#!%*?&

• school Campus Bookshelves
• menu_book Bookshelves
• perm_media Learning Objects
• login Login
• how_to_reg Request Instructor Account
• hub Instructor Commons
• Download Page (PDF)
• Download Full Book (PDF)
• Periodic Table
• Physics Constants
• Scientific Calculator
• Reference & Cite
• Tools expand_more
• Readability

selected template will load here

This action is not available.

2.7: Solving Multi-step Conversion Problems

• Last updated
• Save as PDF
• Page ID 47453

Multiple Conversions

Sometimes you will have to perform more than one conversion to obtain the desired unit. For example, suppose you want to convert 54.7 km into millimeters. We will set up a series of conversion factors so that each conversion factor produces the next unit in the sequence. W e first convert the given amount in km to the base unit, which is meters. We know that 1,000 m =1 km.

Then we convert meters to mm, remembering that \(1\; \rm{mm}\) = \( 10^{-3}\; \rm{m}\).

Concept Map

Calculation

\[ \begin{align*} 54.7 \; \cancel{\rm{km}} \times \dfrac{1,000 \; \cancel{\rm{m}}}{1\; \cancel{\rm{km}}} \times \dfrac{1\; \cancel{\rm{mm}}}{\cancel{10^{-3} \rm{m}}} & = 54,700,000 \; \rm{mm} \\ &= 5.47 \times 10^7\; \rm{mm} \end{align*} \nonumber \]

In each step, the previous unit is canceled and the next unit in the sequence is produced, each successive unit canceling out until only the unit needed in the answer is left.

Example \(\PageIndex{1}\): Unit Conversion

Convert 58.2 ms to megaseconds in one multi-step calculation.

Example \(\PageIndex{2}\): Unit Conversion

How many seconds are in a day?

Exercise \(\PageIndex{1}\)

Perform each conversion in one multi-step calculation.

• 43.007 ng to kg
• 1005 in to ft
• 12 mi to km

Career Focus: Pharmacist

A pharmacist dispenses drugs that have been prescribed by a doctor. Although that may sound straightforward, pharmacists in the United States must hold a doctorate in pharmacy and be licensed by the state in which they work. Most pharmacy programs require four years of education in a specialty pharmacy school. Pharmacists must know a lot of chemistry and biology so they can understand the effects that drugs (which are chemicals, after all) have on the body. Pharmacists can advise physicians on the selection, dosage, interactions, and side effects of drugs. They can also advise patients on the proper use of their medications, including when and how to take specific drugs properly. Pharmacists can be found in drugstores, hospitals, and other medical facilities. Curiously, an outdated name for pharmacist is chemist , which was used when pharmacists formerly did a lot of drug preparation, or compounding . In modern times, pharmacists rarely compound their own drugs, but their knowledge of the sciences, including chemistry, helps them provide valuable services in support of everyone’s health.

In multi-step conversion problems, the previous unit is canceled for each step and the next unit in the sequence is produced, each successive unit canceling out until only the unit needed in the answer is left.

• ‹ Prev
• Next ›

1.1 Problems and Problem Solving

1.2 types and kinds of problems, 1.3 novice versus expert problem solvers/problem solving heuristics, 1.4 chemistry problems, 1.4.1 problems in stoichiometry, 1.4.2 problems in organic chemistry, 1.5 the present volume, 1.5.1 general issues in problem solving in chemistry education, 1.5.2 problem solving in organic chemistry and biochemistry, 1.5.3 chemistry problem solving under specific contexts, 1.5.4 new technologies in problem solving in chemistry, 1.5.5 new perspectives for problem solving in chemistry education, chapter 1: introduction − the many types and kinds of chemistry problems.

• Published: 17 May 2021
• Special Collection: 2021 ebook collection Series: Advances in Chemistry Education Research
• Open the Chapter PDF for in another window
• Get permissions
• Cite Icon Cite

G. Tsaparlis, in Problems and Problem Solving in Chemistry Education: Analysing Data, Looking for Patterns and Making Deductions, ed. G. Tsaparlis, The Royal Society of Chemistry, 2021, ch. 1, pp. 1-14.

Download citation file:

• Ris (Zotero)
• Reference Manager

Problem solving is a ubiquitous skill in the practice of chemistry, contributing to synthesis, spectroscopy, theory, analysis, and the characterization of compounds, and remains a major goal in chemistry education. A fundamental distinction should be drawn, on the one hand, between real problems and algorithmic exercises, and the differences in approach to problem solving exhibited between experts and novices on the other. This chapter outlines the many types and kinds of chemistry problems, placing particular emphasis on studies in quantitative stoichiometry problems and on qualitative organic chemistry problems (reaction mechanisms, synthesis, and spectroscopic identification of structure). The chapter concludes with a brief look at the contents of this book, which we hope will act as an appetizer for more systematic study.

According to the ancient Greeks, “The beginning of education is the study of names”, meaning the “examination of terminology”. 1 The word “problem” (in Greek: «πρόβλημα » /“ problēma” ) derives from the Greek verb “ proballein ” (“pro + ballein”), meaning “to throw forward” ( cf. ballistic and ballistics ), and also “to suggest”, “to argue” etc. Hence, the initial meaning of a “ problēma ” was “something that stands out”, from which various other meanings followed, for instance that of “a question” or of “a state of embarrassment”, which are very close to the current meaning of a problem . Among the works of Aristotle is that of “ Problēmata ”, which is a collection of “why” questions/problems and answers on “medical”, “mathematical”, “astronomical”, and other issues, e.g. , “Why do the changes of seasons and the winds intensify or pause and decide and cause the diseases?” 1  

Problem solving is a complex set of activities, processes, and behaviors for which various models have been used at various times. Specifically, “problem solving is a process by which the learner discovers a combination of previously learned rules that they can apply to achieve a solution to a new situation (that is, the problem)”. 2   Zoller identifies problem solving, along with critical thinking and decision making, as high-order cognitive skills, assuming these capabilities to be the most important learning outcomes of good teaching. 3   Accordingly, problem solving is an integral component in students’ education in science and Eylon and Linn have considered problem solving as one of the major research perspectives in science education. 4  

Bodner made a fundamental distinction between problems and exercises, which should be emphasized from the outset (see also the Foreword to this book). 5–7   For example, many problems in science can be simply solved by the application of well-defined procedures ( algorithms ), thus turning the problems into routine/algorithmic exercises. On the other hand, a real/novel/authentic problem is likely to require, for its solution, the contribution of a number of mental resources. 8  

According to Sternberg, intelligence can best be understood through the study of nonentrenched ( i.e. , novel) tasks that require students to use concepts or form strategies that differ from those they are accustomed to. 9   Further, it was suggested that the limited success of the cognitive-correlates and cognitive-components approaches to measuring intelligence are due in part to the use of tasks that are more entrenched (familiar) than would be optimal for the study of intelligence.

The division of cognitive or thinking skills into Higher-Order (HOCS/HOTS) and Lower-Order (LOCS/LOTS) 3,10   is very relevant. Students are found to perform considerably better on questions requiring LOTS than on those requiring HOTS. Interestingly, performance on questions requiring HOTS often does not correlate with that on questions requiring LOTS. 10   In a school context, a task can be an exercise or a real problem depending on the subject's expertise and on what had been taught. A task may then be an exercise for one student, but a problem for another student. 11   I return to the issue of HOT/LOTS in Chapters 17 and 18.

Johnstone has provided a systematic classification of problem types, which is reproduced in Table 1.1 . 8   Types 1 and 2 are the “normal” problems usually encountered in academic situations. Type 1 is of the algorithmic exercise nature. Type 2 can become algorithmic with experience or teaching. Types 3 and 4 are more complex, with type 4 requiring very different reasoning from that used in types 1 and 2. Types 5–8 have open outcomes and/or goals, and can be very demanding. Type 8 is the nearest to real-life, everyday problems.

Classification of problems. Reproduced from ref. 8 with permission from the Royal Society of Chemistry.

Problem solving in chemistry, as in any other domain, is a huge field, so one cannot really be an expert in all aspects of it. Complementary to Johnstone's classification scheme, one can also identify the following forms: quantitative problems that involve mathematical formulas and computations, and qualitative ones; problems with missing or extraordinary data, with a unique solution/answer, or open problems with more than one solution; problems that cannot be solved exactly but need mathematical approximations; problems that need a laboratory experiment or a computer or a data bank; theoretical/thought problems or real-life ones; problems that can be answered through a literature search, or need the collaboration of specific experts, etc.

According to Bodner and Herron, “Problem solving is what chemists do, regardless of whether they work in the area of synthesis, spectroscopy, theory, analysis, or the characterization of compounds”. 12   Hancock et al. comment that: “The objective of much of chemistry teaching is to equip learners with knowledge they then apply to solve problems”, 13   and Cooper and Stowe ascertain that “historically, problem solving has been a major goal of chemistry education”. 14   The latter authors argue further that problem solving is not a monolithic activity, so the following activities “could all be (and have been) described as problem solving:

solving numerical problems using a provided equation

proposing organic syntheses of target compounds

constructing mechanisms of reactions

identifying patterns in data and making deductions from them

modeling chemical phenomena by computation

identifying an unknown compound from its spectroscopic properties

However, these activities require different patterns of thought, background knowledge, skills, and different types of evidence of student mastery” 14   (p. 6063).

Central among problem solving models have been those dealing with the differences in problem solving between experts and novices. Experts ( e.g., school and university teachers) are as a rule fluent in solving problems in their own field, but often fail to communicate to their students the required principles, strategies, and techniques for problem solving. It is then no surprise that the differences between experts and novices have been a central theme in problem solving education research. Mathematics came first, in 1945, with the publication of George Polya's classic book “ How to solve it: A new aspect of mathematical method ”: 15  

“The teacher should put himself in the student's place, he should see the student's case, he should try to understand what is going on in the student's mind, and ask a question or indicate a step that could have occurred to the student himself ”.

Polya provided advice on teaching problem solving and proposed a four-stage model that included a detailed list of problem solving heuristics. The four stages are: understand the problem, devise a plan, carry out the plan, and look back . In 1979, Bourne, Dominowski, and Loftus modeled a three-stage process, consisting of preparation, production , and evaluation . 16   Then came the physicists. According to Larkin and Reif, novices look for an algorithm, while experts tend to think conceptually and use general strategies . Other basic differences are: (a) the comprehensive and more complete scheme employed by experts, in contrast to the sketchy one used by novices; and (b) the extra qualitative analysis step usually applied by experts, before embarking on detailed and quantitative means of solution. 17,18   Reif (1981, 1983) suggested further that in order for one to be able to solve problems one must have available: (a) a strategy for problem solving; (b) the right knowledge base, and (c) a good organization of the knowledge base. 18,19  

Chemistry problem solving followed suit providing its own heuristics. Pilot and co-workers proposed useful procedures that include the steps that characterize expert solvers. 20–22   They developed an ordered system of heuristics, which is applicable to quantitative problem solving in many fields of science and technology. In particular, they devised a “ Program of Actions and Methods ”, which consists of four phases, as follows: Phase 1, analysis of the problem; Phase 2, transformation of the problem; Phase 3, execution of routine operations; Phase 4, checking the answer and interpretation of the results. Genya proposed the use of “sequences” of problems of gradually increasing complexity , with qualitative problems being used at the beginning. 23  

Randles and Overton compared novice students with expert chemists in the approaches they used when solving open-ended problems. 24     Open-ended problems are defined as problems where not all the required data are given, where there is no one single possible strategy and where there is no single correct answer to the problem. It was found that: undergraduates adopted a greater number of novice-like approaches and produced poorer quality solutions; academics exhibited expert-like approaches and produced higher quality solutions; the approaches taken by industrial chemists were described as transitional.

Finally, one can justify the differences between novices and experts by employing the concept of working memory (see Chapter 5). Experienced learners can group ideas together to see much information as one ‘ chunk ’, while novice learners see all the separate pieces of information, causing an overload of working memory, which then cannot handle all the separate pieces at once. 25,26  

Chemistry is unique in the diversity of its problems, some of which, such as problems in physical and analytical chemistry, are similar to problems in physics, while others, such problems in stoichiometry, in organic chemistry (especially in reaction mechanisms and synthesis), and in the spectroscopic identification of compounds and of molecular structure, are idiosyncratic to chemistry. We will have more to say about stoichiometry and organic chemistry below, but before that there is a need to refer to three figures whom we consider the originators of the field of chemistry education research: the Americans J. Dudley Herron and Dorothy L. Gabel and the Scot Alex H. Johnstone, for it is not a coincidence that all three dealt with chemistry problem solving.

For Herron, successful problem solvers have a good command of basic facts and principles; construct appropriate representations; have general reasoning strategies that permit logical connections among elements of the problem; and apply a number of verification strategies to ensure that the representation of the problem is consistent with the facts given, the solution is logically sound, the computations are error-free, and the problem solved is the problem presented. 27–29   Gabel has also carried out fundamental work on problem solving in chemistry. 30   For instance, she determined students’ skills and concepts that are prerequisites for solving problems on moles, through the use of analog tasks, and identified specific conceptual and mathematical difficulties. 31   She also studied how problem categorization enhances problem solving achievement. 32   Finally, Johnstone studied the connection of problem solving ability in chemistry (but also in physics and biology) with working memory and information processing. We will deal extensively with his relevant work in this book (see Chapter 5). In the rest of this section, reference will be made to some further foundational research work on problem solving in chemistry.

Working with German 16-year-old students in 1988, Sumfleth found that the knowledge of chemical terms is a necessary but not sufficient prerequisite for successful problem solving in structure-properties relationships and in stoichiometry. 33   In the U.S. it was realized quite early (in 1984) that students often use algorithmic methods without understanding the relevant underlying concepts. 32   Indeed, Nakhleh and Mitchell confirmed later (1993) that little connection existed between algorithmic problem solving skills and conceptual understanding. 34   These authors provided ways to evaluate students along a continuum of low-high algorithmic and conceptual problem solving skills, and admitted that the lecture method teaches students to solve algorithms rather than teaching chemistry concepts. Gabel and Bunce also emphasized that students who have not sufficiently grasped the chemistry behind a problem tend to use a memorized formula, manipulate the formula and plug in numbers until they fit. 30   Niaz compared student performance on conceptual and computational problems of chemical equilibrium and reported that students who perform better on problems requiring conceptual understanding also perform significantly better on problems requiring manipulation of data, that is, computational problems; he further suggested that solving computational problems before conceptual problems would be more conducive to learning, so it is plausible to suggest that students’ ability to solve computational/algorithmic problems is an essential prerequisite for a “progressive transition” leading to a resolution of novel problems that require conceptual understanding. 35–37  

Stoichiometry problems are unique to chemistry and at the same time constitute a stumbling block for many students in introductory chemistry courses, with students often relying on algorithms. A review of some fundamental studies follows.

Hans-Jürgen Schmid carried out large scale studies in 1994 and 1997 in Germany and found that when working on easy-to-calculate problems students tended to invent/create a “non-mathematical” strategy of their own, but changed their strategy when moving from an easy-to-calculate problem to a more difficult one. 38,39   Swedish students were also found to behave in a similar manner. 40   A recent (2016) study with junior pre-service chemistry teachers in the Philippines reported that the most prominent strategy was the (algorithmic) mole method, while very few used the proportionality method and none the logical method. 41  

Lorenzo developed, implemented, and evaluated a useful problem solving heuristic in the case of quantitative problems on stoichiometry and solutions. 42   The heuristic works as a metacognitive tool by helping students to understand the steps involved in problem solving, and further to tackle problems in a systematic way. The approach guides students by means of logical reasoning to make a qualitative representation of the solution to a problem before undertaking calculations, thus using a ‘backwards strategy’.

The problem format can serve to make a problem easier or more difficult. A large scale study with 16-year-old students in the UK examined three stoichiometry problems in a number of ways. 43   In Test A the questions were presented as they had previously appeared on National School Examinations, while in Test B each of the questions on Test A was presented in a structured sequence of four parts. An example of one of the questions from both Test A and Test B is given below.

• Test A. Silver chloride (AgCl) is formed in the following reaction: AgNO 3 + HCl → AgCl + HNO 3 Calculate the maximum yield of solid silver chloride that can be obtained from reacting 25 cm 3 of 2.0 M hydrochloric acid with excess silver nitrate. (AgCl = 143.5)

Test B. Silver chloride (AgCl) is formed in the following reaction:

(a) How many moles of silver chloride can be made from 1 mole of hydrochloric acid?

(b) How many moles are there in 25 cm 3 of 2.0 M hydrochloric acid?

(c) How many moles of silver chloride can be made from the number of moles of acid in (b)?

(d) What is the mass of the number of moles of silver chloride in (c)? (AgCl = 143.5)

Student scores on Test B were significantly higher than those on Test A, both overall and on each of the individual questions, showing that structuring serves to make the questions easier.

Drummond and Selvaratnam examined students’ competence in intellectual strategies needed for solving chemistry problems. 44   They gave students problems in two forms, the ‘standard’ one and one with ‘hint’ questions that suggested the strategies which should be used to solve the problems. Although performance in all test items was poor, it improved for the ‘hint’ questions.

Finally, Gulacar and colleagues studied the differences in general cognitive abilities and domain specific skills of higher- and lower-achieving students in stoichiometry problems and in addition they proposed a novel code system for revealing sources of students’ difficulties with stoichiometry. 45,46   The latter topic is tackled in Chapter 4 by Gulacar, Cox, and Fynewever.

Stoichiometry problems have also a place in organic chemistry, but non-mathematical problem solving in organic chemistry is quite a different story. 47   Studying the mechanisms of organic reactions is a challenging activity. The spectroscopic identification of the structure of organic molecules also requires high expertise and a lot of experience. On the other hand, an organic synthesis problem can be complex and difficult for the students, because the number of pathways by which students could synthesise target substance “X” from starting substance “A” may be numerous. The problem is then very demanding in terms of information processing. In addition, students find it difficult to accept that one starting compound treated with only one set of reagents could lead to more than one correct product. A number of studies have dealt with organic synthesis. 48–50   The following comments from two students echo the difficulties faced by many students (pp. 209–210): 50  

“… having to do a synthesis problem is one of the more difficult things. Having to put everything together and sort of use your creativity, and knowing that I know everything solid to come up with a synthesis problem is difficult… it's just you can remember… you can use H 2 and nickel to add hydrogen to a bond but then there's like four other ways so if you're just looking for like what you react with, you can remember just that one but if you need five options just in case it's one of the other options that's given on the test… So, you have to know like multiple ways… and some things are used to maybe reduce… for example, something is used to reduce like a carboxylic acid and something else, the same thing, is used to reduce an aldehyde but then something else is used to like oxidize”.

Qualitative organic chemistry problems are dealt with in Chapters 6 and 7.

The present volume is the result of contributions from many experts in the field of chemistry education, with a clear focus on what can be identified as problem solving research. We are particularly fortunate that George Bodner , an authority in chemistry problem solving, has written the foreword to this book. (George has also published a review of research on problem solving in chemistry. 8   )

The book consists of eighteen chapters that cover many aspects of problem solving in chemistry and are organized under the following themes: (I) General issues in problem solving in chemistry education; (II) Problem solving in organic chemistry and biochemistry; (III) Chemistry problem solving in specific contexts; (IV) New technologies in problem solving in chemistry, and (V) New perspectives for problem solving in chemistry education. In the rest of this introductory chapter, I present a brief preview of the following contents.

The book starts with a discussion of qualitative reasoning in problem solving in chemistry. This type of reasoning helps us build inferences based on the analysis of qualitative values ( e.g. , high, low, weak, and strong) of the properties and behaviors of the components of a system, and the application of structure–property relationships. In Chapter 2, Talanquer summarizes core findings from research in chemistry education on the challenges that students face when engaging in this type of reasoning, and the strategies that support their learning in this area.

For Graulich, Langner, Vo , and Yuriev (Chapter 3), chemical problem solving relies on conceptual knowledge and the deployment of metacognitive problem solving processes, but novice problem solvers often grapple with both challenges simultaneously. Multiple scaffolding approaches have been developed to support student problem solving, often designed to address specific aspects or content area. The authors present a continuum of scaffolding so that a blending of prompts can be used to achieve specific goals. Providing students with opportunities to reflect on the problem solving work of others – peers or experts – can also be of benefit in deepening students’ conceptual reasoning skills.

A central theme in Gulacar, Cox and Fynewever 's chapter (Chapter 4) is the multitude of ways in which students can be unsuccessful when trying to solve problems. Each step of a multi-step problem can be labeled as a subproblem and represents content that students need to understand and use to be successful with the problem. The authors have developed a set of codes to categorize each student's attempted solution for every subproblem as either successful or not, and if unsuccessful, identifying why, thus providing a better understanding of common barriers to success, illustrated in the context of stoichiometry.

In Chapter 5, Tsaparlis re-examines the “working memory overload hypothesis” and associated with it the Johnstone–El Banna predictive model of problem solving. This famous predictive model is based on the effect of information processing, especially of working-memory capacity on problem solving. Other factors include mental capacity or M -capacity, degree of field dependence/independence, and developmental level/scientific reasoning. The Johnstone–El Banna model is re-examined and situations are explored where the model is valid, but also its limitations. A further examination of the role of the above cognitive factors in problem solving in chemistry is also made.

Proposing reaction mechanisms using the electron-pushing formalism, which is central to the practice and teaching of organic chemistry, is the subject of Chapter 6 by Bahttacharyya . The author argues that MR (Mechanistic Reasoning) using the EPF (Electron-Pushing Formalism) incorporates several other forms of reasoning, and is also considered as a useful transferrable skill for the biomedical sciences and allied fields.

Flynn considers synthesis problems as among the most challenging questions for students in organic chemistry courses. In Chapter 7, she describes the strategies used by students who have been successful in solving synthetic problems. Associated classroom and problem set activities are also described.

We all know that the determination of chemical identity is a fundamental chemistry practice that now depends almost exclusively on the characterization of molecular structure through spectroscopic analysis. This analysis is a day-to-day task for practicing organic chemists, and instruction in modern organic chemistry aims to cultivate such expertise. Accordingly, in Chapter 8, Connor and Shultz review studies that have investigated reasoning and problem solving approaches used to evaluate NMR and IR spectroscopic data for organic structural determination, and they provide a foundation for understanding how this problem solving expertise develops and how instruction may facilitate such learning. The aim is to present the current state of research, empirical insights into teaching and learning this practice, and trends in instructional innovations.

The idea that variation exists within a system and the varied population schema described by Talanquer are the theoretical tools for the study by Rodriguez, Hux, Philips, and Towns , which is reported in Chapter 9. The subject of the study is chemical kinetics in biochemistry, and especially of the action and mechanisms of inhibition agents in enzyme catalysis, where a sophisticated understanding requires students to learn to reason using probability-based reasoning.

In Chapter 10, Phelps, Hawkins and Hunter consider the purpose of the academic chemistry laboratory, with emphasis on the practice of problem solving skills beyond those of an algorithmic mathematical nature. The purpose represents a departure from the procedural skills training often associated with the reason we engage in laboratory work (learning to titrate for example). While technical skills are of course important, if part of what we are doing in undergraduate chemistry courses is to prepare students to go on to undertake research, somewhere in the curriculum there should be opportunities to practice solving problems that are both open-ended and laboratory-based. The history of academic chemistry laboratory practice is reviewed and its current state considered.

Chapter 11 by Broman focuses on chemistry problems and problem solving by employing context-based learning approaches, where open-ended problems focusing on higher-order thinking are explored. Chemistry teachers suggested contexts that they thought their students would find interesting and relevant, e.g. , chocolate, doping, and dietary supplements. The chapter analyses students’ interviews after they worked with the problems and discusses how to enhance student interest and perceived relevance in chemistry, and how students’ learning can be improved.

Team Based Learning (TBL) is the theme of Chapter 12 by Capel, Hancock, Howe, Jones, Phillips , and Plana . TBL is a structured small group collaborative form of learning, where learners are required to prepare for sessions in advance, then discuss and debate potential solutions to problems with their peers. It has been found to be highly effective at facilitating active learning. The authors describe their experience with embedding TBL into their chemistry curricula at all levels, including a transnational degree program with a Chinese university.

The ability of students to learn and value aspects of the chemistry curriculum that delve into the molecular basis of chemical events relies on the use of models/molecular representations, and enhanced awareness of how these models connect to chemical observations. Molecular representations in chemistry is the topic of Chapter 13 by Polifka, Baluyut and Holme , which focuses on technology solutions that enhance student understanding and learning of these conceptual aspects of chemistry.

In Chapter 14, Limniou, Papadopoulos, Gavril, Touni , and Chatziapostolidou present an IR spectra simulation. The software includes a wide range of chemical compounds supported by real IR spectra, allowing students to learn how to interpret an IR spectrum, via a step by step process. The chapter includes a report on a pilot trial with a small-scale face-to-face learning environment. The software is available on the Internet for everyone to download and use.

In Chapter 15, Sigalas explores chemistry problems with computational quantum chemistry tools in the undergraduate chemistry curriculum, the use of computational chemistry for the study of chemical phenomena, and the prediction and interpretation of experimental data from thermodynamics and isomerism to reaction mechanisms and spectroscopy. The pros and cons of a series of software tools for building molecular models, preparation of input data for standard software, and visualization of computational results are discussed.

In Chapter 16, Stamovlasis and Vaiopoulou address methodological and epistemological issues concerning research in chemistry problem solving. Following a short review of the relevant literature with emphasis on methodology and the statistical modeling used, the weak points of the traditional approaches are discussed and a novel epistemological framework based on complex dynamical system theory is described. Notably, research using catastrophe theory provides empirical evidence for these phenomena by modeling and explaining mental overload effects and students’ failures. Examples of the application of this theory to chemistry problem solving is reviewed.

Chapter 17 provides extended summaries of the chapters, including a commentary on the chapters. The chapter also provides a brief coverage of various important issues and topics related to chemistry problem solving that are not covered by other chapters in the book.

Finally, in Chapter 18, a Postscript address two specific problem solving issues: (a) the potential synergy between higher and lower-order thinking skills (HOTS and LOTS,) and (b) When problem solving might descend to chaos dynamics. The synergy between HOTS and LOTS is demonstrated by looking at the contribution of chemistry and biochemistry to overcoming the current coronavirus (COVID-19) pandemic. One the other hand, chaos theory provides an analogy with the time span of the predictive power of problem solving models.

«Ἀρχὴ παιδεύσεως ἡ τῶν ὀνομάτων ἐπίσκεψις» (Archē paedeuseōs hē tōn onomatōn episkepsis). By Antisthenes (ancient Greek philosopher), translated by W. A. Oldfather (1925).

• Campaigning and outreach
• News and events
• Awards and funding
• Privacy policy
• Journals and databases
• Locations and contacts
• Membership and professional community
• Teaching and learning
• Help and legal
• Cookie policy
• Terms and conditions
• Get Adobe Acrobat Reader
• Registered charity number: 207890
• © Royal Society of Chemistry 2023

This Feature Is Available To Subscribers Only

Sign In or Create an Account

Chemistry Steps

All You Need for Organic Chemistry

 Study Guides

Practice Problems

 Quizzes

Over 1000 Practice Questions

Structure and Bonding

• Lewis Structures in Organic Chemistry
• Valency and Formal Charges in Organic Chemistry
• How to Determine the Number of Lone Pairs
• sp 3 , sp 2 , and sp Hybridization in Organic Chemistry with Practice Problems
• How to Quickly Determine The sp 3 , sp 2, and sp Hybridization
• Bond Lengths and Bond Strengths
• VSEPR Theory – Molecular and Electron Geometry of Organic Molecules
• Dipole-dipole, London Dispersion and Hydrogen Bonding Interactions
• Dipole Moment and Molecular Polarity
• Boiling Point and Melting Point in Organic Chemistry
• Boiling Point and Melting Point Practice Problems
• Solubility of Organic Compounds
• General Chemistry Overview Quiz

Molecular Representations

• Bond-Line or Skeletal Structures
• Functional Groups in Organic Chemistry with Practice Problems
• Bond-line, Lewis and Condensed Structures with Practice Problems
• Curved Arrows with Practice Problems
• Resonance Structures in Organic Chemistry with Practice Problems
• How to Choose the More Stable Resonance Structure
• Drawing Complex Patterns in Resonance Structures
• Localized and Delocalized Lone Pairs with Practice Problems
• Molecular Representations Quiz

Acids and Bases

• Acids and Bases – General Chemistry
• Organic Acids and Bases
• Organic acid-base mechanisms
• Acid Strength and pKa
• How to Determine the Position of Equilibrium for an Acid-Base Reaction
• Inductive and Resonance (Mesomeric) Effects
• Factors That Determine the pKa and Acid Strength
• How to Choose an Acid or a Base to Protonate or Deprotonate a Given Compound
• Lewis Acids and Bases
• Basicity of Amines
• Organic Acids and Bases Practice Problems
• Organic Acids and Bases Quiz

Alkanes and Cycloalkanes

• Naming Alkanes by IUPAC nomenclature Rules Practice Problems
• Naming Bicyclic Compounds
• Naming Bicyclic Compounds-Practice Problems
• How to Name a Compound with Multiple Functional Groups
• Primary Secondary and Tertiary Carbon Atoms in Organic Chemistry
• Constitutional or Structural Isomers with Practice Problems
• Degrees of Unsaturation or Index of Hydrogen Deficiency
• The Wedge and Dash Representation
• Sawhorse Projections
• Newman Projections with Practice Problems
• Gauche Conformation, Steric, Torsional Strain Energy Practice Problems
• Ring Strain
• Drawing the Chair Conformation of Cyclohexane
• Ring Flip: Drawing Both Chair Conformations with Practice Problems
• 1,3-Diaxial Interactions and A value for Cyclohexanes
• Ring-Flip: Comparing the Stability of Chair Conformations with Practice Problems
• Cis and Trans Decalin

IUPAC Nomenclature Practice Problems

• IUPAC Nomenclature Summary Quiz
• Alkanes and Cycloalkanes Practice Quiz

Stereochemistry

• How to Determine the R and S Configuration
• The R and S Configuration Practice Problems
• Chirality and Enantiomers
• Diastereomers-Introduction and Practice Problems
• Cis and Trans Stereoisomerism in Alkenes
• E and Z Alkene Configuration with Practice Problems
• Enantiomers Diastereomers the Same or Constitutional Isomers with Practice Problems
• Optical Activity
• Specific Rotation
• Racemic Mixtures
• Enantiomeric Excess (ee): Percentage of Enantiomers from Specific Rotation with Practice Problems
• Symmetry and Chirality. Meso Compounds
• Fischer Projections with Practice Problems
• R and S Configuration in the Fischer Projection
• R and S configuration on Newman projections

R and S Configuration of Allenes

Converting Bond-Line, Newman Projection, and Fischer Projections

• Resolution of Enantiomers: Separate Enantiomers by Converting to Diastereomers
• Stereochemistry Practice Problems Quiz

Energy Changes In Organic Chemistry

• Energy and Organic Chemistry Reactions
• Homolytic and Heterolytic Bond Cleavage
• The Heat of Reaction from Bond Dissociation Energies

Nucleophilic Substitution Reactions

• Introduction to Alkyl Halides
• Nomenclature of Alkyl Halides
• Nucleophilic Substitution Reactions – An Introduction
• All You Need to Know About the S N 2 Reaction Mechanism The S N 2 Mechanism: Kinetics, Thermodynamics, Curved Arrows and Stereochemistry with Practice Problems
• The Stereochemistry of S N 2 Reactions
• The S N 1 Nucleophilic Substitution Reaction
• The S N 1 Mechanism: Kinetics, Thermodynamics, Curved Arrows and Stereochemistry with Practice Problems
• The Substrate and Nucleophile in S N 2 and S N 1 Reactions
• Carbocation Rearrangements in S N 1 Reactions with Practice Problems
• When Is the Mechanism S N 1 or S N 2?
• Reactions of Alcohols with HCl, HBr, and HI Acids
• SOCl 2  and PBr 3  for Conversion of Alcohols to Alkyl Halides
• Alcohols in Substitution Reactions with Tons of Practice Problems
• How to Choose Molecules for Doing S N 2 and S N 1 Synthesis-Practice Problems
• Nucleophilic Substitution and Elimination Practice Quiz

Alkenes: Structure, Stability, and Nomenclature

• Alkenes: Structure and Stability
• Naming Alkenes by IUPAC Nomenclature Rules

Elimination Reactions

• General Features of Elimination
• The E2 Mechanism
• Zaitsev’s Rule – Regioselectivity of E2 Elimination Reactions
• The Hofmann Elimination of Amines and Alkyl Fluorides
• Stereoselectivity of E2 Elimination Reactions
• Stereospecificity of E2 Elimination Reactions
• Elimination Reactions of Cyclohexanes with Practice Problems
• POCl 3 for Dehydration of Alcohols
• The E1 Mechanism with Practice Problems
• Regioselectivity of E1 Reactions
• Stereoselectivity of E1 Reactions
• How to tell if it is E2 or E1 Mechanism
• Dehydration of Alcohols by E1 and E2 Elimination
• Mesylates and Tosylates as Good Leaving Groups
• Mitsunobu Reaction
• S N 1 S N 2 E1 E2 – How to Choose the Mechanism
• The Role of the Solvent in S N 1, S N 2, E1, and E2 Reactions
• S N 1 S N 2 E1 or E2 – the Largest Collection of Practice Problems
• The Hammond Postulate
• The E1cB Elimination Mechanism

Addition Reactions of Alkenes

• Markovnikov’s Rule with Practice Problems
• Acid-Catalyzed Hydration of Alkenes with Practice Problems
• Oxymercuration-Demercuration
• Addition of Alcohols to Alkenes
• Free-Radical Addition of HBr: Anti-Markovnikov Addition
• Hydroboration-Oxidation: The Mechanism
• Hydroboration-Oxidation of Alkenes: Regiochemistry and Stereochemistry with Practice Problems
• Halogenation of Alkenes and Halohydrin Formation
• The Stereochemistry of Alkene Addition Reactions
• Cis product in an anti Addition Reaction of Alkenes
• Ozonolysis of Alkenes with Practice Problems
• Syn Dihydroxylation of Alkenes with KMnO 4 and OsO 4
• Anti Dihydroxylation of Alkenes with MCPBA and Other Peroxides with Practice Problems
• Oxidative Cleavage of Alkenes with KMno 4 and O 3
• Alkene Reactions Practice Problems
• Changing the Position of a Double Bond
• Changing the Position of a Leaving Group
• Alkenes Multi-Step Synthesis Practice Problems
• Alkene Addition Reactions Practice Quiz
• Introduction to Alkynes
• Naming Alkynes by IUPAC Nomenclature Rules – Practice Problems
• Preparation of Alkynes by Elimination Reactions
• Hydrohalogenation of Alkynes
• Acid Catalyzed Hydration of Alkynes with Practice Problems
• Reduction of Alkynes
• Halogenation of Alkynes
• Hydroboration-Oxidation of Alkynes with Practice Problems
• Ozonolysis of Alkynes with Practice Problems
• Alkylation of Terminal Alkynes in Organic Synthesis with Practice Problems
• Alkyne reactions summary practice problems
• Alkyne Synthesis Reactions Practice Problems
• Alkyne Naming and Reactions Practice Quiz

Nuclear Magnetic Resonance (NMR) Spectroscopy

• NMR spectroscopy – An Easy Introduction
• NMR Chemical Shift
• NMR Chemical Shift Range and Value Table
• NMR Number of Signals and Equivalent Protons
• Homotopic Enantiotopic Diastereotopic and Heterotopic
• Homotopic Enantiotopic Diastereotopic Practice Problems
• Integration in NMR Spectroscopy
• Splitting and Multiplicity (N+1 rule) in NMR Spectroscopy
• NMR Signal Splitting N+1 Rule Multiplicity Practice Problems
• 13 C Carbon NMR
• DEPT NMR: Signals and Problem Solving
• NMR Spectroscopy-Carbon-Dept-IR Practice Problems

Organic Structure Determination

• Infrared (IR) Spectroscopy Practice Problems

Radical Reactions

• Initiation Propagation Termination in Radical Reactions
• Selectivity in Radical Halogenation
• Stability of Radicals
• Resonance Structures of Radicals
• Stereochemistry of Radical Halogenation with Practice Problems
• Allylic Bromination by NBS with Practice Problems
• Radical Halogenation in Organic Synthesis

Reactions of Alcohols

• Nomenclature of Alcohols: Naming Alcohols based on IUPAC Rules with Practice Problems
• Preparation of Alcohols via Substitution or Addition Reactions
• Reaction of Alcohols with HCl, HBr and HI Acids
• SOCl 2 and PBr 3 for Conversion of Alcohols to Alkyl Halides
• Alcohols in Substitution Reactions  Practice Problems
• The Oxidation States of Organic Compounds
• LiAlH4 and NaBH4 Carbonyl Reduction Mechanism
• Alcohols from Carbonyl Reductions – Practice Problems
• Grignard Reaction in Preparing Alcohols with Practice Problems
• Grignard Reaction in Organic Synthesis with Practice Problems
• Protecting Groups For Alcohols in Organic Synthesis
• Oxidation of Alcohols: PCC, PDC, CrO 3 , DMP, Swern and All of That
• Diols: Nomenclature, Preparation, and Reactions
• NaIO4 Oxidative Cleavage of Diols
• The Pinacol Rearrangement
• The Williamson Ether Synthesis
• Alcohol Reactions Practice Problems
• Naming Thiols and Sulfides
• Reactions of Thiols
• Alcohols Quiz – Naming, Preparation, and Reactions

Ethers and Epoxides

• Preparation of Epoxides
• Ring-Opening Reactions of Epoxides
• Reactions of Epoxides Practice Problems
• Naming Ethers
• Reactions of Ethers-Ether Cleavage

Conjugated Systems

• Resonance and Conjugated Dienes
• Allylic Carbocations
• 1,2 and 1,4 Electrophilic Addition to Dienes
• Kinetic vs Thermodynamic Control of Electrophilic Addition to Dienes

The Diels-Alder Reaction

• Diels Alder Reaction: Dienes and Dienophiles
• Predict the Products of the Diels-Alder Reaction with Practice Problems
• Endo and Exo products of Diels-Alder Reaction with Practice Problems
• Regiochemistry of the Diels–Alder Reaction with Practice Problems
• Identify the Diene and Dienophile of the Diels-Alder reaction with Practice Problems
• Diels Alder Reaction in Organic Synthesis Practice Problems

Aromatic Compounds

• Naming Aromatic Compounds
• Introduction to Aromatic Compounds
• Benzene – Aromatic Structure and Stability Aromaticity and Huckel’s Rule
• Identify Aromatic, Antiaromatic, or Nonaromatic Compounds
• Frost Circle

Electrophilic Aromatic Substitution

• Electrophilic Aromatic Substitution – The Mechanism
• The Halogenation of Benzene
• The Nitration of Benzene
• The Sulfonation of Benzene
• Friedel-Crafts Alkylation with Practice Problems
• Friedel-Crafts Acylation with Practice Problems
• Vilsmeier-Haack Reaction
• The Alkylation of Benzene by Acylation-Reduction
• Ortho Para Meta in EAS with Practice Problems
• Ortho Para and Meta in Disubstituted Benzenes
• Why Are Halogens Ortho-, Para- Directors yet Deactivators ?
• Limitations of Electrophilic Aromatic Substitution Reactions
• Orientation in Benzene Rings With More Than One Substituent
• Synthesis of Aromatic Compounds From Benzene
• Arenediazonium Salts in Electrophilic Aromatic Substitution
• Reactions at the Benzylic Position
• Benzylic Bromination
• Nucleophilic Aromatic Substitution
• Nucleophilic Aromatic Substitution Practice Problems
• Reactions of Phenols
• Reactions of Aniline
• Meta Substitution on Activated Aromatic Ring
• Electrophilic Aromatic Substitution Practice Problems
• Aromatic Compounds Quiz

Aldehydes and Ketones

• Nomenclature of Aldehydes and Ketones
• Preparation of Aldehydes and Ketones
• Nucleophilic Addition to Carbonyl Groups
• The Addition-Elimination Mechanism
• Reduction of Carbonyl Compounds by Hydride Ion
• Reactions of Aldehydes and Ketones with Water
• Reactions of Aldehydes and Ketones with Alcohols: Acetals and Hemiacetals
• Acetals as Protecting Groups for Aldehydes and Ketones
• Imines from Aldehydes and Ketones with Primary Amines
• Enamines from Aldehydes and Ketones with Secondary Amines
• Reductive Amination
• Reactions of Aldehydes and Ketones with Amines-Practice Problems
• Acetal Hydrolysis Mechanism
• Imine and Enamine Hydrolysis Mechanism
• Reaction of Aldehydes and Ketones with CN Cyanohydrin Formation
• Hydrolysis of Acetals, Imines, and Enamines-Practice Problems
• The Wittig Reaction: Examples and Mechanism
• The Wittig Reaction-Practice Problems
• Aldehydes and Ketones to Carboxylic Acids
• Aldehydes and Ketones Reactions Practice Quiz

Carboxylic Acids and Their Derivatives-Nucleophilic Acyl Substitution

• Preparation of Carboxylic Acids
• Naming Carboxylic Acids
• Naming Nitriles
• Naming Esters
• Naming Carboxylic Acid Derivatives – Practice Problems
• Fischer Esterification
• Ester Hydrolysis by Acid and Base-Catalyzed Hydrolysis
• What is Transesterification?
• Esters Reaction with Amines – The Aminolysis Mechanism
• Ester Reactions Summary and Practice Problems
• Preparation of Acyl (Acid) Chlorides (ROCl)
• Reactions of Acid Chlorides (ROCl) with Nucleophiles
• Reaction of Acyl Chlorides with Grignard and Gilman (Organocuprate) Reagents
• Reduction of Acyl Chlorides by LiAlH 4 , NaBH4, and LiAl(OtBu) 3 H
• Preparation and Reaction Mechanism of Carboxylic Anhydrides
• Amides – Structure and Reactivity
• Naming Amides
• Amides Hydrolysis: Acid and Base-Catalyzed Mechanism
• Amide Dehydration Mechanism by SOCl 2 , POCl 3 , and P 2 O 5
• Amide Reduction Mechanism by LiAlH4
• Amides Preparation and Reactions Summary
• Amides from Carboxylic Acids-DCC and EDC Coupling
• The Mechanism of Nitrile Hydrolysis To Carboxylic Acid
• Nitrile Reduction Mechanism with LiAlH4 and DIBAL to Amine or Aldehyde
• The Mechanism of Grignard and Organolithium Reactions with Nitriles
• Carboxylic Acids to Ketones
• Esters to Ketones
• Carboxylic Acids and Their Derivatives Practice Problems
• Carboxylic Acids and Their Derivatives Quiz

Alpha Carbon Chemistry: Enols and Enolates

• Keto-Enol Tautomerization
• Alpha Halogenation of Enols and Enolates
• The Haloform and Iodoform Reactions
• Alpha Halogenation of Carboxylic Acids
• Alpha Halogenation of Enols and Enolates Practice Problems
• Aldol Reaction – Principles and Mechanism
• Aldol Condensation – Dehydration of Aldol Addition Product
• Intramolecular Aldol Reactions
• Aldol Addition and Condensation Reactions – Practice Problems
• Crossed Aldol And Directed Aldol Reactions
• Crossed Aldol Condensation Practice Problems
• The Cannizzaro reaction
• Alkylation of Enolates Alpha Position
• Enolate Alkylation Practice Problems
• Acetoacetic Ester Synthesis
• Acetoacetic Ester Enolates Practice Problems
• Malonic Ester Synthesis
• Decarboxylation
• Michael Reaction: The Conjugate Addition of Enolates
• Robinson Annulation, Shortcut, and Retrosynthesis
• Claisen Condensation
• Dieckmann condensation – An Intramolecular Claisen Reaction
• Crossed Claisen and Claisen Variation Reactions
• Claisen Condensation Practice Problems
• Stork Enamine Synthesis
• Mannich Reaction
• Enolates in Organic Synthesis – a Comprehensive Practice Problem
• Naming Amines: Systematic and Common Nomenclature
• Preparation of Amines
• The Gabriel Synthesis of Primary Amines
• The Reaction of Amines with Nitrous Acid
• Reactions of Amines Practice Problems
• The Cope elimination
• Boc Protecting Group for Amines

Organic Sy nthesis Problems

• Organic Chemistry Multistep Synthesis Practice Problems
• Organic Synthesis Puzzles
• How to Choose Molecules for Doing SN2 and SN1 Synthesis-Practice Problems

Carbohydrates

• Carbohydrates – Structure and Classification
• Erythro and Threo
• R and S Configuration on Fischer Projections
• D and L Sugars
• Aldoses and Ketoses: Classification and Stereochemistry
• Epimers and Anomers
• Converting Fischer, Haworth, and Chair forms of Carbohydrates
• Mutarotation
• Isomerization of Carbohydrates
• Ether and Ester Derivatives of Carbohydrates
• Oxidation of Monosaccharides
• Reduction of Monosaccharides
• Kiliani–Fischer Synthesis
• Wohl Degradation
• Carbohydrates Practice Problem Quiz

WassUp 1.9.4.5 timestamp: 2024-04-28 11:18:18AM UTC (06:18AM) If above timestamp is not current time, this page is cached.

• Science & Math

Enjoy fast, free delivery, exclusive deals, and award-winning movies & TV shows with Prime Try Prime and start saving today with fast, free delivery

Amazon Prime includes:

Fast, FREE Delivery is available to Prime members. To join, select "Try Amazon Prime and start saving today with Fast, FREE Delivery" below the Add to Cart button.

• Cardmembers earn 5% Back at Amazon.com with a Prime Credit Card.
• Unlimited Free Two-Day Delivery
• Streaming of thousands of movies and TV shows with limited ads on Prime Video.
• A Kindle book to borrow for free each month - with no due dates
• Listen to over 2 million songs and hundreds of playlists
• Unlimited photo storage with anywhere access

Important:  Your credit card will NOT be charged when you start your free trial or if you cancel during the trial period. If you're happy with Amazon Prime, do nothing. At the end of the free trial, your membership will automatically upgrade to a monthly membership.

Buy new: $62.93

Return this item for free.

Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no shipping charges

• Go to your orders and start the return
• Select the return method

Download the free Kindle app and start reading Kindle books instantly on your smartphone, tablet, or computer - no Kindle device required .

Read instantly on your browser with Kindle for Web.

Using your mobile phone camera - scan the code below and download the Kindle app.

Image Unavailable

• To view this video download Flash Player

Chemistry Problem-Solving: A Step-by-Step Approach 1st Edition

Purchase options and add-ons.

• ISBN-10 1465205314
• ISBN-13 978-1465205315
• Edition 1st
• Publisher Kendall Hunt Publishing
• Publication date August 6, 2012
• Language English
• Dimensions 7.99 x 0.87 x 10 inches
• Print length 230 pages
• See all details

Product details

• Publisher ‏ : ‎ Kendall Hunt Publishing; 1st edition (August 6, 2012)
• Language ‏ : ‎ English
• Spiral-bound ‏ : ‎ 230 pages
• ISBN-10 ‏ : ‎ 1465205314
• ISBN-13 ‏ : ‎ 978-1465205315
• Item Weight ‏ : ‎ 1 pounds
• Dimensions ‏ : ‎ 7.99 x 0.87 x 10 inches
• #697 in Analytic Chemistry (Books)
• #4,630 in Chemistry (Books)
• #217,651 in Unknown

Customer reviews

Customer Reviews, including Product Star Ratings help customers to learn more about the product and decide whether it is the right product for them.

To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzed reviews to verify trustworthiness.

• Sort reviews by Top reviews Most recent Top reviews

Top reviews from the United States

There was a problem filtering reviews right now. please try again later..

• Amazon Newsletter
• About Amazon
• Accessibility
• Sustainability
• Press Center
• Investor Relations
• Amazon Devices
• Amazon Science
• Sell on Amazon
• Sell apps on Amazon
• Supply to Amazon
• Protect & Build Your Brand
• Become an Affiliate
• Become a Delivery Driver
• Start a Package Delivery Business
• Advertise Your Products
• Self-Publish with Us
• Become an Amazon Hub Partner
• › See More Ways to Make Money
• Amazon Visa
• Amazon Store Card
• Amazon Secured Card
• Amazon Business Card
• Shop with Points
• Credit Card Marketplace
• Reload Your Balance
• Amazon Currency Converter
• Your Account
• Your Orders
• Shipping Rates & Policies
• Amazon Prime
• Returns & Replacements
• Manage Your Content and Devices
• Recalls and Product Safety Alerts
• Conditions of Use
• Privacy Notice
• Consumer Health Data Privacy Disclosure
• Your Ads Privacy Choices

The Cognitive Orbit

Revolve Around Wisdom with SDPUO

How to Calculate Moles in Chemistry: A Step-by-Step Guide

Introduction

Chemistry is a fascinating and complex subject that helps us understand the world around us. One of the most important concepts in chemistry is the calculation of moles. Moles are a unit of measurement used to express the number of particles in a substance. Understanding how to calculate moles is essential for anyone studying chemistry because it enables them to make accurate predictions about chemical reactions and solve real-world problems.

A Step-by-Step Guide to Calculating Moles in Chemistry

What is a mole.

Before we dive into the calculations, let’s define what a mole is. A mole is the amount of a substance that contains the same number of particles as there are atoms in 12 grams of pure carbon-12. This number is known as Avogadro’s number, which is approximately 6.02 x 10^23.

Calculating Moles: The Formula

To calculate the number of moles in a substance, we use the following formula:

moles = mass / molar mass

The mass refers to the amount of the substance, and the molar mass is the mass of one mole of the substance, which can be found on the periodic table.

Step-by-Step Instructions

Let’s say we want to find the number of moles in 10 grams of sodium chloride (NaCl). Here are the step-by-step instructions:

1. Find the molar mass of NaCl on the periodic table. We see that the molar mass of NaCl is 58.44 g/mol.

2. Divide the mass of NaCl by its molar mass to get the number of moles. In this case, 10 grams divided by 58.44 g/mol is 0.171 moles.

Visual Aids

Sometimes, visuals can help us understand complex concepts better. Here is a helpful diagram that shows the steps involved in calculating moles:

The Importance of Calculating Moles in Chemical Reactions

Mole calculations are essential for predicting the outcomes of chemical reactions. By knowing the number of moles of reactants and products, chemists can determine how much of each substance is needed for a reaction to occur, how much of each substance will be produced, and the overall yield of the reaction.

Real-World Examples

Mole calculations are used in real-world situations every day. For example, in the food industry, chemists use mole calculations to determine the amount of ingredients needed to make a certain number of servings of a product. In medicine, mole calculations are used to determine the concentration of a drug in a patient’s bloodstream.

Common Mistakes to Avoid When Calculating Moles

Like with any type of calculation, there are common pitfalls to avoid when calculating moles. One of the most common mistakes is using the wrong conversion factor or not accounting for significant figures.

Tips for Avoiding Mistakes

To avoid mistakes, it’s important to use the correct conversion factor and pay attention to significant figures. Always double-check your calculations and be mindful of any rounding errors.

Real-World Examples of Mole Calculations

Let’s look at some practical examples of how to use mole calculations to solve everyday problems.

Calculating Concentration

Suppose you have a solution that contains 25 grams of sodium chloride (NaCl) dissolved in 500 milliliters of water. To calculate the concentration of the solution, we use the following formula:

concentration (in moles per liter) = moles of solute / volume of solution (in liters)

1. Calculate the number of moles of NaCl.

moles = mass / molar mass = 25 g / 58.44 g/mol = 0.427 moles

2. Convert the volume of the solution from milliliters to liters.

volume = 500 mL / 1000 mL/L = 0.5 L

3. Now we can calculate the concentration.

concentration = 0.427 mol / 0.5 L = 0.854 M

Therefore, the concentration of the solution is 0.854 moles per liter.

How to Convert Between Moles and Other Units of Measurement

It’s possible to convert between moles, grams, atoms, and other units of measurement. Understanding how to convert between these units is crucial for performing accurate mole calculations.

The Conversions

Here are the formulas for converting between moles, grams, and atoms:

grams = moles x molar mass

atoms = moles x Avogadro’s number

Let’s say we want to convert 5 grams of methane (CH4) to moles.

1. Find the molar mass of methane. We can do this by adding up the molar masses of the elements that make up the compound: 4 x 1.0079 (the molar mass of hydrogen) + 1 x 12.0107 (the molar mass of carbon) = 16.0425 g/mol.

2. Plug in the values: moles = 5 g / 16.0425 g/mol = 0.3118 moles.

Mastering Mole Calculations: Practice Problems and Solutions

The best way to master mole calculations is through practice. Here are some practice problems to help you build your skills:

1. How many moles are in 25 grams of ammonium nitrate (NH4NO3)?

2. What is the molar mass of magnesium sulfate (MgSO4)?

3. How many grams of copper (II) chloride (CuCl2) are needed to make 0.2 moles of the compound?

Why Moles Matter: Exploring the Role of Moles in the Periodic Table and Beyond

Mole calculations have played a significant role in the development of the periodic table and our understanding of the properties of different elements. By understanding how to calculate moles, chemists can predict the behavior of elements in various chemical reactions and make new discoveries.

Mole calculations are an integral part of chemistry. By understanding what a mole is and how to perform calculations, you can solve real-world problems and make accurate predictions about chemical reactions. Remember to avoid common mistakes, practice often, and continue to explore the fascinating world of chemistry.

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

Related News

The Ultimate Guide to Cooking Steak in a Pan: Tips, Tricks, and Delicious Recipes

The Ultimate Guide to Making Chimichurri Sauce: A Step-by-Step Recipe

You may have missed.

How to Check Cortisol Levels: A Beginner’s Guide to At-Home Testing

How to Make a Beacon: A Step-by-Step Guide to Design, Assemble, and Install

How to Unblock on Snapchat: A Step-by-Step Guide

How to Reset an iPad Without a Password: A Comprehensive Guide

News, Views & Insights

• Best of Blog (70)
• Astronomy (28)
• Computational Thinking (64)
• Current Events (36)
• Data Analysis and Visualization (138)
• Data Repository (11)
• Design (24)
• Developer Insights (76)
• Digital Humanities (7)
• Education (191)
• Events (44)
• Finance (24)
• Function Repository (12)
• Geosciences (12)
• High-Performance Computing (12)
• History (18)
• Image Processing (48)
• Machine Learning (16)
• Mathematica News (112)
• Mathematica Q&A (13)
• Mathematics (129)
• New Technology (41)
• Other Application Areas (133)
• Raspberry Pi (18)
• Recreational Computation (163)
• Software Development (35)
• System Modeler (49)
• Uncategorized (1)
• Wolfram Cloud (24)
• Wolfram Community (19)
• Wolfram Demonstrations Project (31)
• Wolfram Language (296)
• Wolfram News (278)
• Wolfram Notebooks (37)
• Wolfram U (27)
• Wolfram|Alpha (48)
• Wolfram|One (7)

Navigating Quantum Computing: Accelerating Next-Generation Innovation

Food and sun: wolfram language recipe graphs for the solar eclipse, computational astronomy: exploring the cosmos with wolfram, quantum chemistry: step-by-step chemistry series.

After working our way through chemical reactions , solutions and structure and bonding , we close out our step-by-step chemistry series with quantum chemistry. Quantum chemistry is the application of quantum mechanics to atoms and molecules in order to understand their properties.

Have you ever wondered why the periodic table is structured the way it is or why chemical bonds form in the first place? The answers to those questions and many more come from quantum chemistry. Wolfram|Alpha and its step-by-step chemistry offerings won’t make the wave-particle duality any less weird, but they will help you connect chemical properties to the underlying quantum mechanical behavior.

The step-by-step solutions provide stepwise guides that can be viewed one step at a time or all at once while working through a problem. Read on for example problems covering orbital diagrams, frequency and wavelength conversions, and mass-energy equivalence.

Orbital Diagrams

One fundamental aspect of chemistry is understanding where electrons live in atoms. Building orbital diagrams provides a good way to visualize this information. The step-by-step solution provides a general framework for solving this class of problems in the Plan step. Details of how to represent the information graphically, along with explanations of core electrons, are provided. An explanation of how many electrons a given orbital set can hold is available via the “Show intermediate steps” button.

Example Problem

Build the orbital diagram for elemental iron .

Step-by-Step Solution

For this class of problem, just enter “ orbital diagram for elemental iron ”.

Frequency & Wavelength Conversion

Electromagnetic radiation is central to many techniques in analytical chemistry. Converting frequency and wavelength is a critical skill for understanding theoretical models and interpreting experimental spectra. The photon wavelength calculator provides instructions for interconversion of the frequency and wavelength of electromagnetic radiation.

A sodium streetlight gives off yellow light with a wavelength of 598 nm. What is the frequency of this light?

The calculator can be fed known information directly via “ photon wavelength lambda=598 nm ”.

Mass-Energy Equivalence

The nuclear binding energy is useful when tracking energy changes in nuclear reactions. Converting between mass and energy is a key step in computing nuclear binding energies. The relativistic energy calculator provides instructions for converting between mass and energy.

The calculator can be fed known information directly via “ relativistic energy m=0.0304 u ”.

Challenge Problems

Test your problem-solving skills by using the Wolfram|Alpha tools described to solve these word problems on quantum chemistry. Answers will be provided at the end of this post!

• Use an orbital diagram to predict the electron configuration of the P 3– anion.
• The Trinity test released 5.5 × 10 26 MeV. What mass is equivalent to this energy?

Answers to Last Week’s Challenge Problems

Here are the answers to last week’s challenge problems on structure and bonding.

1. What is the oxidation state of hydrogen in lithium aluminum hydride?

Recall that oxidation state and oxidation number are the same. Additionally, recall that Wolfram|Alpha computes all oxidation numbers in a molecule. Note that “ hydrogen oxidation state lithium aluminum hydride ” actually returns results for both hydrogen (H 2 ) and lithium aluminum hydride.

What is the orbital hybridization of the central atom in SF 6 ?

Wolfram|Alpha determines the hybridization for all elements except hydrogen (it only has one orbital and therefore cannot hybridize) in a molecule. So you would just need to determine that S is the central atom.

Answers to the Quantum Chemistry Challenge Problems

1. use an orbital diagram to predict the electron configuration of the p 3– anion..

Wolfram|Alpha generates orbital diagrams for neutral atoms in their ground state. However, the neutral atom diagram can be used to figure out where additional electrons will go or which electrons might be removed the easiest. In this case, three extra electrons need to be added to make the trianion.

The electron configuration for the phosphorus trianion is 3s 2 3p 6 .

2. The Trinity test released 5.5 x 10 26 MeV. What mass is equivalent to this energy?

The mass-energy equivalence calculator can be used to solve this, but now the energy must be passed in rather than the mass.

We hope you’ve enjoyed reading our step-by-step chemistry series, and that our review of chemical reactions , solutions and structure and bonding , along with today’s post on quantum chemistry, have been useful in your studies. New step-by-step solution offerings for chemistry are always rolling out; equilibrium constant expressions , rate-of-reaction expressions, electron configurations , valence electrons , reaction thermochemistry and solution pH are just some of the areas on the to-do list. So stay tuned and check back frequently!

! Please enter your comment (at least 5 characters).

! Please enter your name.

! Please enter a valid email address.

Related Posts

Introducing Chemistry AI Homework Solver: The Ultimate Solution for Your Chemistry Assignments!

Are you struggling with your chemistry homework? Are you tired of spending hours trying to solve complex equations and formulas? Look no further! Smodin Chemistry Homework Solver is here to help you ace your assignments with ease.

How does it work?

Our AI-powered tool uses advanced algorithms and machine learning to provide accurate and efficient solutions to your chemistry problems. Simply input your assignment or question, and Smodin Chemistry AI homework solver will generate step-by-step solutions in seconds.

Why choose Chemistry AI Homework Solver?

• Save Time: With our solver, you can complete your assignments in a fraction of the time it would take you to solve them manually.
• Accuracy: Smodin’s Chemistry homework solver provides accurate solutions every time, eliminating the risk of errors and mistakes.
• Boost your Grades: You can enhance your school success by guaranteeing the precision and correctness of your responses using Smodin’s AI Chemistry solver.
• Convenience: 24/7 availability guarantees that you can access it at any time for your chemistry homework needs.

Experience the Best Chemistry AI Homework Solver

Smodin’s Chemistry AI Homework Solver is the most advanced and reliable solution for all your chemistry assignments. Whether you're a high school or college student, Smodin can help you tackle even the most challenging problems. Give it a try today and experience the convenience and accuracy of Smodin Chemistry solver. Say goodbye to the frustration of chemistry homework and hello to success!

Get Instant Help with Chemistry Questions Using Smodin’s AI-powered Chemistry Solver!

Are you stuck on a chemistry question and don't know where to turn for help? Smodin’s Chemistry AI Solver is here to assist you. With our advanced algorithms, we can provide accurate and efficient solutions to your chemistry problems in no time. Say goodbye to frustration and confusion and hello to quick and easy answers to your chemistry questions.

Ace Your Exams with the Help of Smodin’s Chemistry Homework Assistant!

Preparing for a chemistry exam can be stressful and time-consuming. Let Smodin’s Chemistry Homework Assistant take some of the weight off your shoulders. With Smodin you can practice solving problems and reviewing concepts to ensure that you're fully prepared for your exam. Smodin’s assistant can help you achieve your academic goals and excel in your chemistry studies.

The Benefits of Using a Chemistry AI Solver for Your Homework

Using a Chemistry AI Solver for your homework has many benefits. Not only can it save you time and provide accurate solutions, but it can also improve your understanding of chemistry concepts. Smodin Chemistry AI solver generates step-by-step solutions, allowing you to learn from the process and apply it to future assignments. Try Smodin homework solver today and see the difference it can make in your academic performance.

Say Goodbye to Late-Night Study Sessions with Smodin’s Chemistry Question Solver

Late-night study sessions can be exhausting, especially when you're struggling with chemistry problems. Let Smodin Chemistry Question Solver lighten the load. Smodin can provide quick and accurate answers to your questions, allowing you to complete your assignments faster and more efficiently. Get the rest you need and the academic success you deserve with the help of Smodin’s solver.

Solver Title

Generating PDF...

• Pre Algebra Order of Operations Factors & Primes Fractions Long Arithmetic Decimals Exponents & Radicals Ratios & Proportions Percent Modulo Number Line Expanded Form Mean, Median & Mode
• Algebra Equations Inequalities System of Equations System of Inequalities Basic Operations Algebraic Properties Partial Fractions Polynomials Rational Expressions Sequences Power Sums Interval Notation Pi (Product) Notation Induction Logical Sets Word Problems
• Pre Calculus Equations Inequalities Scientific Calculator Scientific Notation Arithmetics Complex Numbers Polar/Cartesian Simultaneous Equations System of Inequalities Polynomials Rationales Functions Arithmetic & Comp. Coordinate Geometry Plane Geometry Solid Geometry Conic Sections Trigonometry
• Calculus Derivatives Derivative Applications Limits Integrals Integral Applications Integral Approximation Series ODE Multivariable Calculus Laplace Transform Taylor/Maclaurin Series Fourier Series Fourier Transform
• Functions Line Equations Functions Arithmetic & Comp. Conic Sections Transformation
• Linear Algebra Matrices Vectors
• Trigonometry Identities Proving Identities Trig Equations Trig Inequalities Evaluate Functions Simplify
• Statistics Mean Geometric Mean Quadratic Mean Average Median Mode Order Minimum Maximum Probability Mid-Range Range Standard Deviation Variance Lower Quartile Upper Quartile Interquartile Range Midhinge Standard Normal Distribution
• Physics Mechanics
• Chemistry Chemical Reactions Chemical Properties
• Finance Simple Interest Compound Interest Present Value Future Value
• Economics Point of Diminishing Return
• Conversions Roman Numerals Radical to Exponent Exponent to Radical To Fraction To Decimal To Mixed Number To Improper Fraction Radians to Degrees Degrees to Radians Hexadecimal Scientific Notation Distance Weight Time Volume
• Pre Algebra
• Pre Calculus
• Linear Algebra
• Trigonometry
• Conversions

Most Used Actions

Number line.

• x^{2}-x-6=0
• -x+3\gt 2x+1
• line\:(1,\:2),\:(3,\:1)
• prove\:\tan^2(x)-\sin^2(x)=\tan^2(x)\sin^2(x)
• \frac{d}{dx}(\frac{3x+9}{2-x})
• (\sin^2(\theta))'
• \lim _{x\to 0}(x\ln (x))
• \int e^x\cos (x)dx
• \int_{0}^{\pi}\sin(x)dx
• \sum_{n=0}^{\infty}\frac{3}{2^n}
• Is there a step by step calculator for math?
• Symbolab is the best step by step calculator for a wide range of math problems, from basic arithmetic to advanced calculus and linear algebra. It shows you the solution, graph, detailed steps and explanations for each problem.
• Is there a step by step calculator for physics?
• Symbolab is the best step by step calculator for a wide range of physics problems, including mechanics, electricity and magnetism, and thermodynamics. It shows you the steps and explanations for each problem, so you can learn as you go.
• How to solve math problems step-by-step?
• To solve math problems step-by-step start by reading the problem carefully and understand what you are being asked to find. Next, identify the relevant information, define the variables, and plan a strategy for solving the problem.
• Practice Makes Perfect Learning math takes practice, lots of practice. Just like running, it takes practice and dedication. If you want...

Please add a message.

Message received. Thanks for the feedback.

Social science takes the stage in a live storytelling event at the Cantor Arts Center

Stanford researchers shared stories of psychotic breaks, economic disparities, and criminal justice reform at an event Tuesday hosted by Stanford Impact Labs in collaboration with The Story Collider.

Dr. Rania Awaad retells the event that encouraged her to pursue a career in psychiatry. (Image credit: Christine Baker)

Late one night years ago, Rania Awaad and her husband were at home when they heard a loud and sudden knock at their front door. When they opened it, Awaad saw a young woman she’d met before at their local Muslim community center.

“Before I could say anything, she runs right past me into the apartment,” Awaad, now a clinical professor of psychiatry and behavioral sciences at Stanford’s School of Medicine, recalled on Tuesday evening at a show titled Testing Ground Live! Social Science on Stage , held at the Cantor Arts Center.

Awaad shared how she and her husband found the woman ducked behind their couch, her eyes wide and terrified. “I need to speak to the imam, my religious leader!” the woman said. Awaad told her that the imam was not in their apartment.

Moments later the woman ran out of the apartment to the community center across the street, still searching for the imam. After deliberating on how to help the woman, some members at the center began to pray for her. Meanwhile, Awaad’s husband contacted a community elder.

“This is a psychotic episode,” the elder said. “She needs to go to the emergency room.”

The woman eventually got the help she needed, but the event left a lasting impact on Awaad, who was struck that no one at the center recognized the woman’s psychiatric emergency and her need for medical attention.

It made Awaad, who was a fourth-year medical student studying to become an obstetrician, realize the importance of mental health, and led her to switch her studies to psychiatry.

Tuesday’s event was hosted by Stanford Impact Labs (SIL) in collaboration with The Story Collider . It featured Stanford researchers like Awaad, a former SIL design fellow , sharing stories of pivotal moments in their lives that changed how they approached their work in mental health, digital literacy, and criminal justice reform, among other societal issues.

SIL is a cross-university initiative that launched in the 2019-20 academic year as part of the university’s  Long-range Vision  to train and support researchers to serve the public good by using data-driven, social science research to develop actionable ways to address pernicious and pervasive social problems.

Hannah Melville-Rea, a PhD student from Australia, shares what she’s learned about America’s home insurance system and the impact it has on various communities. (Image credit: Christine Baker)

Wild wild west

Another presenter was Hannah Melville-Rea, a PhD student from Australia. At Stanford, she’s studying environment and resources at the Stanford Doerr School of Sustainability, is a Knight-Hennessy Scholar, and was a 2023 SIL Summer PhD Fellow . Taking the stage, she shared that to better understand America’s home insurance system and how (or whether) it serves communities impacted by significant flood risk, she attended two local events. The first was a workshop in Menlo Park for residents to learn how to get the most out of their insurance. She recalled expensive cars parked outside the event. Inside were tables with Tiffany-blue tablecloths and appetizers.

“I look around the room at the other attendees. Everyone is white. Everyone is over the age of 65. I think everyone knows each other because they only asked me to introduce myself,” Melville-Rea recalled.

“I realize this [event] is only applicable if you’re a homeowner with insurance,” she said.

A couple of weeks later, Melville-Rea attended a crowded community meeting in East Palo Alto where residents shared their frustration with flooding and a lack of support from FEMA, the Federal Emergency Management Agency, tasked with responding to natural disasters.

“I cannot get over how different these two community meetings were [and] only three miles apart,” she said. “Up the hill, a bunch of homeowners with good insurance, who honestly, probably could weather a storm without it. Down the road, a bunch of renters who we now know had no insurance, who are really at the frontlines of these climate impacts, and now they’re being ghosted by FEMA.”

She said that as an Australian, she assumed the government would always step in to provide quality security for residents, regardless of their economic status. But she was surprised to learn the opposite was true in the United States.

“We live in the wild west. It is up to the individual. Everyone needs their own safety net,” she said. “And we urgently need to get everyone insurance.”

Alex Chohlas-Wood speaks at Testing Ground Live! Social Science on Stage at the Cantor Arts Center. (Image credit: Christine Baker)

High stakes decisions

Alex Chohlas-Wood is the executive director of the Computational Policy Lab (CPL), which has twice been funded by SIL and where he uses technology and data science to support criminal justice reform. He spoke about a pilot project he worked on for the San Francisco District Attorney’s office focused on “race-blind charging.” The idea, he explained, was to develop an artificial intelligence tool that could automatically redact race-related information from police reports that prosecutors review when deciding whether to charge or dismiss a crime.

His team got to work developing an algorithm for redacting potential indicators of race in police reports, including names and addresses. By the summer of 2019, they had a reliable system, but the project was cut short due to the COVID-19 pandemic. Officials in Yolo County, California expressed interest in the system, so Chohlas-Wood’s team developed one for their district attorney.

“He was so excited about this idea, that he got his own legislator to write a bill mandating that all prosecutors across the state of California use race blind charging by the beginning of 2025,” Chohlas-Wood said.

In 2022, the bill passed unanimously in both state houses and Governor Newsom signed it into law. Chohlas-Wood said he was excited to see his work lead to such meaningful policy changes.

“At the same time, I felt a real sense of responsibility to make sure this thing was done right, and to make sure that we could actually evaluate its impacts and charging decisions – really high stakes decisions – that prosecutors make, that can have profound impacts on people’s lives,” he said.

The next steps CPL is taking to evaluate and scale race-blind charging across California have been funded by a Stanford Impact Labs Stage 2 investment .

In total, six storytellers shared five stories on stage at Tuesday’s event. Recordings of each will soon be available on SIL’s website .