Question 1

Counting the number of moles on both the reactant and product sides of an equation is the first step in balancing the equation.

Accepted Answer

A) True 
 B)False

Question 2

One gram of gold (atomic mass 197 amu) contains more atoms than one gram of copper (atomic mass 63.55 amu).

Accepted Answer

A) True 
 B)False

Question 3

Which of the following statements concerning a voltaic cell is FALSE?

Accepted Answer

A) The oxidation half reaction occurs at the cathode. 
B) A voltaic cell uses an oxidation-reduction reaction to produce electrical energy. 
C) The cell consists of two half cells. 
D) The anode and the cathode are separated by a salt bridge. 
E) At the anode a substance will lose electrons. 
A) The oxidation half reaction occurs at the cathode. 
B) A voltaic cell uses an oxidation-reduction reaction to produce electrical energy. 
C) The cell consists of two half cells. 
D) The anode and the cathode are separated by a salt bridge. 
E) At the anode a substance will lose electrons.

Question 4

What is the mass of 3.5 × 1022 molecules of CO2?

Accepted Answer

A) 5.9 × 10-2 g 
B) 2.6 g 
C) 1.8 × 1024 g 
D) 1.5 × 10-3 g 
E) 3.9 g 
A) 5.9 × 10-2 g 
B) 2.6 g 
C) 1.8 × 1024 g 
D) 1.5 × 10-3 g 
E) 3.9 g

Question 5

The mass of one atom of oxygen is 16.00 amu.What is the mass of one mole of elemental oxygen (O2)?

Accepted Answer

A) 32.00 amu 
B) 32.00 g 
C) 9.64 × 1024 g 
D) 1.93 × 1025 g 
E) 1.88 × 1022 g 
A) 32.00 amu 
B) 32.00 g 
C) 9.64 × 1024 g 
D) 1.93 × 1025 g 
E) 1.88 × 1022 g

Question 6

In electrolysis, electrical energy is used to drive a non-spontaneous oxidation-reduction reaction to occur.

Accepted Answer

A) True 
 B)False

Question 7

The unbalanced equation for the combustion of octane, a component of gasoline, is shown below.What would be the coefficient of carbon dioxide once the equation is balanced? C8H18(l) + O2(g) → CO2(g) + H2O(l)

Accepted Answer

A) 8 
B) 25 
C) 16 
D) 18 
E) No coefficient would be shown. 
A) 8 
B) 25 
C) 16 
D) 18 
E) No coefficient would be shown.

Question 8

How many atoms of sulfur are present in a 155 g sample of sulfur? [Molar mass: S, 32.06 g/mol]

Accepted Answer

A) 2.91 × 1024 atoms 
B) 6.02 × 1023 atoms 
C) 3.01 × 1023 atoms 
D) 2.91 × 1023 atoms 
E) 2.01 × 1023 atoms 
A) 2.91 × 1024 atoms 
B) 6.02 × 1023 atoms 
C) 3.01 × 1023 atoms 
D) 2.91 × 1023 atoms 
E) 2.01 × 1023 atoms

Question 9

The symbol ∆, above or below the reaction arrow in an equation, indicates that heating is needed for the reaction to take place.

Accepted Answer

A) True 
 B)False

Question 10

What is the mass of one mole of diatomic hydrogen, H2?

Accepted Answer

A) 1.01 amu 
B) 2.02 amu 
C) 1.01 g 
D) 2.02 g 
E) 6.022 × 1023 g 
A) 1.01 amu 
B) 2.02 amu 
C) 1.01 g 
D) 2.02 g 
E) 6.022 × 1023 g

Question 11

Classify the following reaction: H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(aq)

Accepted Answer

A) precipitation 
B) acid - base 
C) oxidation - reduction 
D) decomposition 
E) combustion 
A) precipitation 
B) acid - base 
C) oxidation - reduction 
D) decomposition 
E) combustion

Question 12

Choose the best classification of the reaction represented by the following equation: 2Fe3+(aq) + Fe(s) → 3Fe2+(aq)

Accepted Answer

A) combustion 
B) decomposition 
C) acid-base 
D) oxidation-reduction 
E) precipitation 
A) combustion 
B) decomposition 
C) acid-base 
D) oxidation-reduction 
E) precipitation

Question 13

Cis-platin is a chlorine-containing chemotherapy agent with the formula Pt(NH3)2Cl2.What is the mass of one mole of cis-platin?

Accepted Answer

A) 283.02 g/mol 
B) 286.05 g/mol 
C) 300.06 g/mol 
D) 488.91 g/mol 
E) 492.37 g/mol 
A) 283.02 g/mol 
B) 286.05 g/mol 
C) 300.06 g/mol 
D) 488.91 g/mol 
E) 492.37 g/mol

Question 14

The chemical equation below is not balanced.Balance the equation, then determine which statement concerning the balanced equation is TRUE. KClO3(s) → KCl(s) + O2(g)

Accepted Answer

A) The balanced equation will have an equal number of moles of reactants and products. 
B) The balanced equation will have three atoms of oxygen on each side. 
C) The balanced equation will have one atom of potassium on each side. 
D) The balanced equation will have two atoms of chlorine on each side. 
E) The balanced equation will contain a substance whose coefficient is 1. 
A) The balanced equation will have an equal number of moles of reactants and products. 
B) The balanced equation will have three atoms of oxygen on each side. 
C) The balanced equation will have one atom of potassium on each side. 
D) The balanced equation will have two atoms of chlorine on each side. 
E) The balanced equation will contain a substance whose coefficient is 1.

Question 15

How is the reaction shown below best classified? 2HgO(s) → 2Hg(l) + O2(g)

Accepted Answer

A) decomposition 
B) combination 
C) single-replacement 
D) double-replacement 
E) combustion 
A) decomposition 
B) combination 
C) single-replacement 
D) double-replacement 
E) combustion

Question 16

What is the mass of one mole of carbon atoms?

Accepted Answer

A) 6.022 g 
B) 12.01 g 
C) 7.232 g 
D) 6.022 × 1023 g 
E) 7.232 × 1024 g 
A) 6.022 g 
B) 12.01 g 
C) 7.232 g 
D) 6.022 × 1023 g 
E) 7.232 × 1024 g

Question 17

Choose the best classification of the reaction represented by the following equation: HBr(aq) + KOH(aq) → KBr(aq) + H2O(l)

Accepted Answer

A) combustion 
B) combination 
C) precipitation 
D) decomposition 
E) acid-base 
A) combustion 
B) combination 
C) precipitation 
D) decomposition 
E) acid-base

Question 18

The term "molecular mass" is appropriately used for covalent compounds, but not ionic compounds.

Accepted Answer

A) True 
 B)False

Question 19

Consider the following precipitation reaction.Which of the following correctly identifies the spectator ions in this reaction? Na2S(aq) + CuSO4(aq) → Na2SO4(aq) + CuS(s)

Accepted Answer

A) Na2+, S2-, Cu2+, and SO42- 
B) Na+, S2-, Cu2+, and SO42- 
C) Na+ and SO42- 
D) Cu2+ and S2- 
E) There are no spectator ions present. 
A) Na2+, S2-, Cu2+, and SO42- 
B) Na+, S2-, Cu2+, and SO42- 
C) Na+ and SO42- 
D) Cu2+ and S2- 
E) There are no spectator ions present.

Question 20

Aluminum metal and oxygen gas are produced when aluminum oxide is heated at high temperature.Which statement concerning this chemical change is true?

Accepted Answer

A) Aluminum oxide is the product in this reaction. 
B) This reaction is a combustion reaction. 
C) Aluminum and oxygen are the reactants in this reaction. 
D) This reaction is a decomposition reaction. 
E) The chemical equation for this reaction is: AlO2(s) → Al(s) + O2(g). 
A) Aluminum oxide is the product in this reaction. 
B) This reaction is a combustion reaction. 
C) Aluminum and oxygen are the reactants in this reaction. 
D) This reaction is a decomposition reaction. 
E) The chemical equation for this reaction is: AlO2(s) → Al(s) + O2(g).

Exam 4: Calculations, Chemical Changes, and the Chemical Equation

Counting the number of moles on both the reactant and product sides of an equation is the first step in balancing the equation.

One gram of gold (atomic mass 197 amu) contains more atoms than one gram of copper (atomic mass 63.55 amu).

Which of the following statements concerning a voltaic cell is FALSE?

What is the mass of 3.5 × 1022 molecules of CO2?

The mass of one atom of oxygen is 16.00 amu.What is the mass of one mole of elemental oxygen (O2)?

In electrolysis, electrical energy is used to drive a non-spontaneous oxidation-reduction reaction to occur.

The unbalanced equation for the combustion of octane, a component of gasoline, is shown below.What would be the coefficient of carbon dioxide once the equation is balanced? C8H18(l) + O2(g) → CO2(g) + H2O(l)

How many atoms of sulfur are present in a 155 g sample of sulfur? [Molar mass: S, 32.06 g/mol]

The symbol ∆, above or below the reaction arrow in an equation, indicates that heating is needed for the reaction to take place.

What is the mass of one mole of diatomic hydrogen, H2?

Classify the following reaction: H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(aq)

Choose the best classification of the reaction represented by the following equation: 2Fe3+(aq) + Fe(s) → 3Fe2+(aq)

Cis-platin is a chlorine-containing chemotherapy agent with the formula Pt(NH3)2Cl2.What is the mass of one mole of cis-platin?

The chemical equation below is not balanced.Balance the equation, then determine which statement concerning the balanced equation is TRUE. KClO3(s) → KCl(s) + O2(g)

How is the reaction shown below best classified? 2HgO(s) → 2Hg(l) + O2(g)

What is the mass of one mole of carbon atoms?

Choose the best classification of the reaction represented by the following equation: HBr(aq) + KOH(aq) → KBr(aq) + H2O(l)

The term "molecular mass" is appropriately used for covalent compounds, but not ionic compounds.

Consider the following precipitation reaction.Which of the following correctly identifies the spectator ions in this reaction? Na2S(aq) + CuSO4(aq) → Na2SO4(aq) + CuS(s)

Aluminum metal and oxygen gas are produced when aluminum oxide is heated at high temperature.Which statement concerning this chemical change is true?

Chemistry:methods and Measurement

The Structure of the Atom and the Periodic Table

Structure and Properties of Ionic and Covalent Compounds

States of Matter- Gases, Liquids, and Solids

Solutions

Energy, Rate and Equilibrium

Acids and Bases

The Nucleus, Radioactivity, and Nuclear Medicine

An Introduction to Organic Chemistry- the Saturated Hydrocarbons

The Unsaturated Hydrocarbons- Alkenes, Alkynes, and Aromatics

Alcohols, Phenols, Thiols, and Ethers

Aldehydes and Ketones

Carboxylic Acids and Carboxylic Acid Derivatives

Amines and Amides

Carbohydrates

Lipids and Their Functions in Biochemical Systems

Protein Structure and Function

Enzymes

Introduction to Molecular Genetics

Carbohydrate Metabolism

Aerobic Respiration and Energy Production

Fatty Acid Metabolism

Filters

What is the mass of 3.5 × 10²² molecules of CO₂?

The mass of one atom of oxygen is 16.00 amu.What is the mass of one mole of elemental oxygen (O₂)?

The unbalanced equation for the combustion of octane, a component of gasoline, is shown below.What would be the coefficient of carbon dioxide once the equation is balanced? C₈H₁₈(l) + O₂(g) → CO₂(g) + H₂O(l)

What is the mass of one mole of diatomic hydrogen, H₂?

Classify the following reaction: H₂SO₄(aq) + 2KOH(aq) → K₂SO₄(aq) + 2H₂O(aq)

Choose the best classification of the reaction represented by the following equation: 2Fe³⁺(aq) + Fe(s) → 3Fe²⁺(aq)

Cis-platin is a chlorine-containing chemotherapy agent with the formula Pt(NH₃)₂Cl₂.What is the mass of one mole of cis-platin?

The chemical equation below is not balanced.Balance the equation, then determine which statement concerning the balanced equation is TRUE. KClO₃(s) → KCl(s) + O₂(g)

How is the reaction shown below best classified? 2HgO(s) → 2Hg(l) + O₂(g)

Choose the best classification of the reaction represented by the following equation: HBr(aq) + KOH(aq) → KBr(aq) + H₂O(l)

Consider the following precipitation reaction.Which of the following correctly identifies the spectator ions in this reaction? Na₂S(aq) + CuSO₄(aq) → Na₂SO₄(aq) + CuS(s)