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Tutorials & Exercises

Math Review

Exponents: These are simple exercises where numbers in Scientific Notation are multiplied or divided and you are required to enter the value of the exponent.

Percentage Calculations: This is a simple exercise in calculating and manipulating percentages.

Direct and Inverse Proportionality: This is a simple exercise in manipulating proportionalities.

Chapter 1

Significant Figures: These are simple exercises requiring you to identify the number of significant figures in a variety of integer and decimal numbers.

Scientific & Decimal Notation: A number will be shown in either exponential or decimal notation; you are required to convert to the other format.

Simple Metric Conversions: A number and a metric unit will be shown in either exponential or decimal notation; you are required to convert the unit to the other format.

Atomic Configuration of Elements & Ions: A variety of elements and ions are shown and you are required to enter the proper number of protons, electrons and neutrons.

Electronic Configuration of Simple Elements: A variety of elements from the first three periods are shown and you are required to enter the proper electronic configuration.

Chapter 2

Density Calculations-I: Simple problems are given involving density calculations using common units.

Density Calculations-II: Word problems are given involving density calculations, and generally requiring the interconversion of metric units.

Mass Interconversions: In this problem set you are presented with a problem involving the conversion of masses from the English system to the Metric system.

Volume Interconversions: In this problem set you are presented with a problem involving the conversion of volumes from the English system to the Metric system.

Density Interconversions: In this problem set you are given a density using one measure of mass & volume and you are required to convert this into a different mass/volume relationship. This is a good exercise in the interconversion of metric units.

Chapter 3

Writing Formulas from Chemical Names: Names of a variety of molecular and ionic compounds are given and you are required to enter the chemical formula.

Flash Cards - Ionic: A variety of ionic compounds are presented as "Flash Cards" with the chemical name on the following card.

Naming Ionic Compounds: A variety of ionic compounds are presented and you are required to enter the chemical name.

Naming Molecular Compounds: A variety of molecular compounds are presented and you are required to enter the chemical name.

Lewis Structures: The formula for a compound is given. You are then led through a series of simple steps to construct an acceptable Lewis structure.

Chapter 4

Converting between Moles & Mass: The number of moles of a compound, or a mass, is given and you are required to calculate the other quantity.

Mole-Mass Conversions II: The number of moles of a compound, a mass, or the molar mass is given and you are required to calculate the missing quantity.

Mole-Mass Formula: A chemical formula is given and you are required to calculate data for some element.

Calculating Percentage Composition: Data are presented for a compound and you use this to calculate the mass percentage for each element.

Moles & Mass Quiz: A simple multiple choice quiz covering mole/mass conversions, etc.

Chapter 5

Balancing Chemical Equations: A series of chemical equations are presented and you are required to enter coefficients to properly balance them.

Calculating Oxidation Numbers in Chemical Compounds: Simple chemical compounds are given and you are required to calculate the oxidation number of a selected element.

Oxidation and Reduction Reactions: Simple chemical reactions and half-reactions are given and you are required to determine if oxidation or reduction has occurred.

Chapter 6

Chemical Stoichiometry: A balanced equation is given along with a molar quantity for one reactant or product; you are required to calculate the molar quantity of a second reactant or product.

Using Mass Ratios to Solve Simple Stoichiometry Problems: A balanced equation is given along with a molar quantity for one reactant or product; you are required to calculate the molar quantity of a second reactant or product using the Mass Ratio method.

Limiting Reactant Problems solved using the Mass Ratio Method: A balanced equation is given along with a molar quantity for the reactants; you are required to identify the limiting reactant using the Mass Ratio method.

Percentage Yield: A balanced equation is given along with a molar quantity for one reactant or product; you are required to calculate the percentage yield in the reaction.

Chapter 7

Molarity Problems: An exercise in performing standard molarity calculations.

Molarity Problems-II: More advanced exercises involving mass, molarity and dilution problems.

Dilution of Solutions: In this problem set you are required to calculate volumes or concentrations for simple dilution problems.

Chapter 8

Basic pH Problems: Basic exercises in converting between pH, [H⁺] and [HO^-].

pH Problems: An exercise in converting between pH, pOH, [H⁺] and [HO^-].

Conjugate Acid-Base Pairs: An exercise in conjugate acids & bases in simple hydrolysis reactions.

Chapter 9

Boyle's Law: A series of problems involving pressure-volume calculations, and generally requiring the interconversion of metric units.

Charles's Law: A series of problems involving pressure-volume calculations, and generally requiring the interconversion of metric units.

The Ideal Gas Law: A series of problems involving pressure-volume-temperature-mole calculations (PV = nRT), and generally requiring the interconversion of metric units.

Combined Gas Laws: A series of problems involving pressure-volume/pressure-temperature calculations, and generally requiring the interconversion of metric units.

Chapter 10

Calculating Equilibrium Constants: A chemical equation is given along with equilibrium concentrations; you are required to calculate the equilibrium constant.

Converting K_c and K_p: A chemical equation is given along with a value for K_c and a temperature; you are required to calculate K_p.

Using ICE Tables to Calculate K: A chemical equation is given along with equilibrium values; you are required to use an ICE Table to calculate K.

The pH of Weak Acid & Base Solutions: A concentration of a weak acid or base is given and you are required to use the ionization constant to calculate the pH of the solution.

Buffer Calculations: Using the Henderson-Hasselbach equation, you are required to calculate buffer concentrations or the resulting pH of the solution.

Chemistry 112 Tutorials:

Combining Equilibrium Expressions: A series of equilibrium expressions are given; you are required to combine these to obtain the desired equilibrium constant.

Acid-Base Equilibria: In this exercise, you will take equilibrium values for two weak acids and combine them to get a net equilibrium constant for the combined acid-base reaction.

Buffer Properties: You are given a buffer solution with a fixed acid-base ratio. Strong acid or base is then added. Using the Henderson-Hasselbach equation, you are required to calculate the resulting pH of the solution.

Nuclear Equations: You are given a hypothetical nuclear decay process and you must enter the starting or final nuclide.