Question 1

Which of the following must we know to write the equilibrium constant for a chemical reaction?

Accepted Answer

A)  the balanced chemical equation for the reaction 
B)  the rate at which the reaction occurs 
C)  the diameter of the vessel in which the reaction occurs 
D)  the activation energy of the reaction 
A)  the balanced chemical equation for the reaction 
B)  the rate at which the reaction occurs 
C)  the diameter of the vessel in which the reaction occurs 
D)  the activation energy of the reaction

Question 2

In an energy diagram for a chemical reaction, what species represents the highest energy?

Accepted Answer

A)  the catalyst 
B)  the products 
C)  the reactants 
D)  the transition state 
A)  the catalyst 
B)  the products 
C)  the reactants 
D)  the transition state

Question 3

Consider the following energy diagram for a reaction.   Which letter represents the transition state?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 4

Which of the following is true of fevers?

Accepted Answer

A)  An increase in body temperature never has beneficial effects. 
B)  A 1°C increase in temperature is a protective mechanism. 
C)  A 5°C increase in temperature is never fatal. 
D)  None of these are true. 
A)  An increase in body temperature never has beneficial effects. 
B)  A 1°C increase in temperature is a protective mechanism. 
C)  A 5°C increase in temperature is never fatal. 
D)  None of these are true.

Question 5

A particular chemical reaction carried out at 60°C takes 4 hours. Approximately how long will it take to carry out the reaction at 30°C?

Accepted Answer

A)  0.5 hour 
B)  8 hours 
C)  4 hours 
D)  16 hours 
A)  0.5 hour 
B)  8 hours 
C)  4 hours 
D)  16 hours

Question 6

If the endothermic reaction   has reached equilibrium, what is the effect of raising the temperature of the reaction vessel?

Accepted Answer

A)  The reaction will shift from the left to the right. 
B)  The reaction will shift from the right to the left. 
C)  There will be no further reaction. 
D)  Whether the reaction will shift to the left or the right depends on the initial temperature. 
A)  The reaction will shift from the left to the right. 
B)  The reaction will shift from the right to the left. 
C)  There will be no further reaction. 
D)  Whether the reaction will shift to the left or the right depends on the initial temperature.

Question 7

For which of the following reactions is it important that the species collide with the correct orientation?

Accepted Answer

A)  2NO(g) + O2(g) → 2NO2(g) 
B)  HCl(g) + H2O(l) → H3O+(aq) + Cl-(aq) 
C)  both of these 
D)  neither of these 
A)  2NO(g) + O2(g) → 2NO2(g) 
B)  HCl(g) + H2O(l) → H3O+(aq) + Cl-(aq) 
C)  both of these 
D)  neither of these

Question 8

Which of the following is true of a reaction that has reached equilibrium?

Accepted Answer

A)  The reactants have been completely converted to products. 
B)  The rate of the forward reaction is faster than the rate of the reverse reaction. 
C)  The rate of the forward reaction is equal to the rate of the reverse reaction. 
D)  The rate of the forward reaction is slower than the rate of the reverse reaction. 
A)  The reactants have been completely converted to products. 
B)  The rate of the forward reaction is faster than the rate of the reverse reaction. 
C)  The rate of the forward reaction is equal to the rate of the reverse reaction. 
D)  The rate of the forward reaction is slower than the rate of the reverse reaction.

Question 9

What is the effect of adding CH3COOH(g) to a container in which the reaction has reached equilibrium?

Accepted Answer

A)  The reaction will shift in the forward direction. 
B)  The reaction will shift in the reverse direction. 
C)  There will be no effect. 
D)  The reaction will reach quasi-equilibrium. 
A)  The reaction will shift in the forward direction. 
B)  The reaction will shift in the reverse direction. 
C)  There will be no effect. 
D)  The reaction will reach quasi-equilibrium.

Question 10

Suppose that the equilibrium constant for the chemical reaction is 2.8 x 107.   What is the equilibrium constant for the following reaction?

Accepted Answer

A)  3.6 × 10-8 
B)  2.1 × 10-4 
C)  4.8 × 103 
D)  3.3 × 107 
A)  3.6 × 10-8 
B)  2.1 × 10-4 
C)  4.8 × 103 
D)  3.3 × 107

Question 11

In a certain chemical reaction, 1.00 g of product is produced in 15 min when the reaction is carried out at 20°C. Assuming that there is sufficient starting material available, approximately how much product will be produced in the same length of time if the reaction is carried out in a boiling water bath at 100°C?

Accepted Answer

A)  2.00 g 
B)  16.0 g 
C)  64.0 g 
D)  256 g 
A)  2.00 g 
B)  16.0 g 
C)  64.0 g 
D)  256 g

Question 12

For the reaction   , which of the following is the equilibrium constant expression?

Accepted Answer

A)  K = [H2][N2]/[NH3] 
B)  K = [NH3]/[H2][N2] 
C)  K = [H2]3[N2]/[NH3]2 
D)  K = [NH3]2/[H2]3[N2] 
A)  K = [H2][N2]/[NH3] 
B)  K = [NH3]/[H2][N2] 
C)  K = [H2]3[N2]/[NH3]2 
D)  K = [NH3]2/[H2]3[N2]

Question 13

A catalyst speeds up a chemical reaction as a result of which of the following?

Accepted Answer

A)  It increases the number of collisions between reacting molecules. 
B)  It makes the reaction more endothermic. 
C)  It makes the reaction more exothermic. 
D)  none of these 
A)  It increases the number of collisions between reacting molecules. 
B)  It makes the reaction more endothermic. 
C)  It makes the reaction more exothermic. 
D)  none of these

Question 14

Which of the following is not true of activation energy?

Accepted Answer

A)  Decreasing the activation energy decreases the reaction rate. 
B)  Decreasing the activation energy increases the reaction rate. 
C)  The activation energy is the minimum energy required for a reaction to occur. 
D)  The activation energy of an endothermic reaction is positive. 
A)  Decreasing the activation energy decreases the reaction rate. 
B)  Decreasing the activation energy increases the reaction rate. 
C)  The activation energy is the minimum energy required for a reaction to occur. 
D)  The activation energy of an endothermic reaction is positive.

Question 15

Which of the following statements is true of a reversible reaction?

Accepted Answer

A)  All reversible reactions are exothermic. 
B)  All reversible reactions are endothermic. 
C)  When we mix the reactants together, one or more of the reactants will be completely used up. 
D)  When we mix the reactants together, none of the reactants will be completely used up. 
A)  All reversible reactions are exothermic. 
B)  All reversible reactions are endothermic. 
C)  When we mix the reactants together, one or more of the reactants will be completely used up. 
D)  When we mix the reactants together, none of the reactants will be completely used up.

Question 16

Potassium hydroxide and phosphorus pentachloride react to form potassium phosphate and potassium chloride. Which of the following will result in the fastest reaction between potassium hydroxide and phosphorus pentachloride?

Accepted Answer

A)  Crystals of the two reactants are placed in a mortar and are ground. 
B)  Large crystals of the two reactants are placed in contact with one another. 
C)  Powdered samples of the two reactants are mixed together. 
D)  Solutions of the two reactants are mixed together. 
A)  Crystals of the two reactants are placed in a mortar and are ground. 
B)  Large crystals of the two reactants are placed in contact with one another. 
C)  Powdered samples of the two reactants are mixed together. 
D)  Solutions of the two reactants are mixed together.

Question 17

Which of the following is the best definition of a catalyst?

Accepted Answer

A)  A catalyst is a substance that speeds up the rate of a chemical reaction till its concentration is reduced to zero. 
B)  A catalyst is a substance that speeds up the rate of a chemical reaction without participating in the reaction. 
C)  A catalyst is a substance that speeds up the rate of a chemical reaction without being consumed during the reaction. 
D)  All of these are equally good definitions. 
A)  A catalyst is a substance that speeds up the rate of a chemical reaction till its concentration is reduced to zero. 
B)  A catalyst is a substance that speeds up the rate of a chemical reaction without participating in the reaction. 
C)  A catalyst is a substance that speeds up the rate of a chemical reaction without being consumed during the reaction. 
D)  All of these are equally good definitions.

Question 18

For the reaction A + B → 2C, which of the following best describes how we can measure the reaction rate?

Accepted Answer

A)  The rate can be measured by measuring how fast A is produced. 
B)  The rate can be measured by measuring how fast C is produced. 
C)  The rate can be measured by measuring how fast B is produced. 
D)  The rate can be measured by measuring how fast C is consumed. 
A)  The rate can be measured by measuring how fast A is produced. 
B)  The rate can be measured by measuring how fast C is produced. 
C)  The rate can be measured by measuring how fast B is produced. 
D)  The rate can be measured by measuring how fast C is consumed.

Question 19

Which of the following statements is true of the reaction A + B → 2C?

Accepted Answer

A)  B is consumed at the same rate that A is consumed. 
B)  C is produced at twice the rate A is consumed. 
C)  B is consumed at the same rate that A is consumed and C is produced at twice the rate A is consumed. 
D)  None of these are true. 
A)  B is consumed at the same rate that A is consumed. 
B)  C is produced at twice the rate A is consumed. 
C)  B is consumed at the same rate that A is consumed and C is produced at twice the rate A is consumed. 
D)  None of these are true.

Question 20

Given that the reaction C(s) + O2(g) → CO2(g) is exothermic, which of the following is true of the reaction CO2(g) → C(s) + O2(g)?

Accepted Answer

A)  Its activation energy is lower than that of C(s) + O2(g) → CO2(g). 
B)  Its activation energy is the same as that of C(s) + O2(g) → CO2(g). 
C)  Its activation energy is higher than that of C(s) + O2(g) → CO2(g). 
D)  There is no relationship between its activation energy and that of C(s) + O2(g) → CO2(g). 
A)  Its activation energy is lower than that of C(s) + O2(g) → CO2(g). 
B)  Its activation energy is the same as that of C(s) + O2(g) → CO2(g). 
C)  Its activation energy is higher than that of C(s) + O2(g) → CO2(g). 
D)  There is no relationship between its activation energy and that of C(s) + O2(g) → CO2(g).

Exam 7: Reaction Rates and Chemical Equilibrium

Which of the following must we know to write the equilibrium constant for a chemical reaction?

In an energy diagram for a chemical reaction, what species represents the highest energy?

Consider the following energy diagram for a reaction. Which letter represents the transition state?

Which of the following is true of fevers?

A particular chemical reaction carried out at 60°C takes 4 hours. Approximately how long will it take to carry out the reaction at 30°C?

If the endothermic reaction has reached equilibrium, what is the effect of raising the temperature of the reaction vessel?

For which of the following reactions is it important that the species collide with the correct orientation?

Which of the following is true of a reaction that has reached equilibrium?

What is the effect of adding CH3COOH(g) to a container in which the reaction has reached equilibrium?

Suppose that the equilibrium constant for the chemical reaction is 2.8 x 107. What is the equilibrium constant for the following reaction?

For the reaction , which of the following is the equilibrium constant expression?

A catalyst speeds up a chemical reaction as a result of which of the following?

Which of the following is not true of activation energy?

Which of the following statements is true of a reversible reaction?

Potassium hydroxide and phosphorus pentachloride react to form potassium phosphate and potassium chloride. Which of the following will result in the fastest reaction between potassium hydroxide and phosphorus pentachloride?

Which of the following is the best definition of a catalyst?

For the reaction A + B → 2C, which of the following best describes how we can measure the reaction rate?

Which of the following statements is true of the reaction A + B → 2C?

Given that the reaction C(s) + O2(g) → CO2(g) is exothermic, which of the following is true of the reaction CO2(g) → C(s) + O2(g)?

Matter, Energy, and Measurement

Atoms

Chemical Bonds

Chemical Reactions

Gases, Liquids, and Solids

Solutions and Colloids

Acids and Bases

Nuclear Chemistry

Organic Chemistry

Alkanes

Alkenes, Alkynes, and Aromatic Compounds

Alcohols, Ethers, and Thiols

Chirality: the Handedness of Molecules

Amines

Aldehydes and Ketones

Carboxylic Acids

Carboxylic Anhydrides, Esters, and Amides

Carbohydrates

Lipids

Proteins

Enzymes

Chemical Communications: Neurotransmitters and Hormones

Nucleotides, Nucleic Acids, and Heredity

Gene Expression and Protein Synthesis

Bioenergetics: How the Body Converts Food to Energy

Specific Catabolic Pathways: Carbohydrate, Lipid, and Protein Metabolism

Biosynthetic Pathways

Nutrition

Immunochemistry

Body Fluids

Filters

What is the effect of adding CH₃COOH(g) to a container in which the reaction has reached equilibrium?

Suppose that the equilibrium constant for the chemical reaction is 2.8 x 10⁷. What is the equilibrium constant for the following reaction?

Given that the reaction C(s) + O₂(g) → CO₂(g) is exothermic, which of the following is true of the reaction CO₂(g) → C(s) + O₂(g)?