Question 1

What is the effect of increasing the temperature at which a reaction is carried out?

Accepted Answer

A)  In all cases, the rate of reaction decreases. 
B)  In virtually all cases, the rate of reaction decreases. 
C)  In all cases, the rate of reaction increases. 
D)  In virtually all cases, the rate of reaction increases. 
A)  In all cases, the rate of reaction decreases. 
B)  In virtually all cases, the rate of reaction decreases. 
C)  In all cases, the rate of reaction increases. 
D)  In virtually all cases, the rate of reaction increases.

Question 2

Consider the following energy diagram for a reaction.   Which letter represents the activation energy of the reaction?

Accepted Answer

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

Question 3

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

Accepted Answer

A)  HCl(g) + H2O(l) → H2O+(aq) + Cl-(aq) 
B)  Ag+(aq) + Cl-(aq) → AgCl(s) 
C)  both of these 
D)  neither of these 
A)  HCl(g) + H2O(l) → H2O+(aq) + Cl-(aq) 
B)  Ag+(aq) + Cl-(aq) → AgCl(s) 
C)  both of these 
D)  neither of these

Question 4

In an energy diagram for an exothermic chemical reaction, which of the following is true?

Accepted Answer

A)  The energy of the products is lower than that of the reactants. 
B)  The energy of the transition state is higher than that of the reactants. 
C)  The energy of the products is lower than that of the reactants and the energy of the transition state is higher than that of the reactants. 
D)  None of these. 
A)  The energy of the products is lower than that of the reactants. 
B)  The energy of the transition state is higher than that of the reactants. 
C)  The energy of the products is lower than that of the reactants and the energy of the transition state is higher than that of the reactants. 
D)  None of these.

Question 5

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

Accepted Answer

A)  It increases the number of collisions among reacting molecules. 
B)  It makes the reaction more endothermic. 
C)  It makes the reaction more exothermic. 
D)  It provides an alternative reaction pathway. 
A)  It increases the number of collisions among reacting molecules. 
B)  It makes the reaction more endothermic. 
C)  It makes the reaction more exothermic. 
D)  It provides an alternative reaction pathway.

Question 6

Consider a sample of water in a closed container. When the physical process   has reached equilibrium, what can we say about any specific water molecule?

Accepted Answer

A)  If it was present in the liquid phase, then it will always remain in the liquid phase. 
B)  If it was present in the vapor phase, then it will always remain in the vapor phase. 
C)  It will sometimes be in the liquid phase and sometimes be in the vapor phase. 
D)  If it was present in the liquid phase, then it will always remain in the liquid phase, and if it was present in the vapor phase, then it will always remain in the vapor phase. 
A)  If it was present in the liquid phase, then it will always remain in the liquid phase. 
B)  If it was present in the vapor phase, then it will always remain in the vapor phase. 
C)  It will sometimes be in the liquid phase and sometimes be in the vapor phase. 
D)  If it was present in the liquid phase, then it will always remain in the liquid phase, and if it was present in the vapor phase, then it will always remain in the vapor phase.

Question 7

For the exothermic reaction   making which of the following changes will ensure that the reaction will not shift either to the left or to the right?

Accepted Answer

A)  removing NH3 and adding H2 and N2 
B)  removing NH3 and lowering the temperature 
C)  removing NH3 and raising the temperature 
D)  removing NH3 and decreasing the volume of the beaker 
A)  removing NH3 and adding H2 and N2 
B)  removing NH3 and lowering the temperature 
C)  removing NH3 and raising the temperature 
D)  removing NH3 and decreasing the volume of the beaker

Question 8

Which of the following is true of most multistep reactions?

Accepted Answer

A)  Most of them involve the participation of only two reactant molecules. 
B)  They are all endothermic reactions. 
C)  They are all exothermic reactions. 
D)  The rate of reaction is usually determined by the slowest step. 
A)  Most of them involve the participation of only two reactant molecules. 
B)  They are all endothermic reactions. 
C)  They are all exothermic reactions. 
D)  The rate of reaction is usually determined by the slowest step.

Question 9

To which of the following systems does Le Chatelier's principle apply?

Accepted Answer

A)  a system in which the reaction is moving in the forward direction 
B)  a system in which the reaction is moving in the reverse direction 
C)  a system that has reached equilibrium 
D)  a system that is about to reach equilibrium 
A)  a system in which the reaction is moving in the forward direction 
B)  a system in which the reaction is moving in the reverse direction 
C)  a system that has reached equilibrium 
D)  a system that is about to reach equilibrium

Question 10

Which of the following best describes the rates of chemical reactions?

Accepted Answer

A)  Most chemical reactions occur very slowly. 
B)  Most chemical reactions occur at moderate rates. 
C)  Most chemical reactions occur very rapidly. 
D)  Chemical reactions have a wide range of rates, from extremely fast to extremely slow. 
A)  Most chemical reactions occur very slowly. 
B)  Most chemical reactions occur at moderate rates. 
C)  Most chemical reactions occur very rapidly. 
D)  Chemical reactions have a wide range of rates, from extremely fast to extremely slow.

Question 11

In a particular chemical reaction, three bonds are broken and four bonds are formed. Based on this information alone, which of the following is true?

Accepted Answer

A)  The reaction has a high activation energy. 
B)  The reaction is endothermic. 
C)  The reaction is exothermic. 
D)  We cannot determine which of the statements is true. 
A)  The reaction has a high activation energy. 
B)  The reaction is endothermic. 
C)  The reaction is exothermic. 
D)  We cannot determine which of the statements is true.

Question 12

Which of the following is true of effective collisions?

Accepted Answer

A)  The number of effective collisions decreases as the temperature increases. 
B)  The number of effective collisions determines the rate of a reaction. 
C)  The number of effective collisions is independent of the orientation of the molecules. 
D)  The number of effective collisions determines the phases of the reactants. 
A)  The number of effective collisions decreases as the temperature increases. 
B)  The number of effective collisions determines the rate of a reaction. 
C)  The number of effective collisions is independent of the orientation of the molecules. 
D)  The number of effective collisions determines the phases of the reactants.

Question 13

Which of the following units can used to describe the rate of a chemical reaction?

Accepted Answer

A)  (mol·L)/min 
B)  (mol/L)/min 
C)  1/(mol·L·min) 
D)  (mol·L)·min 
A)  (mol·L)/min 
B)  (mol/L)/min 
C)  1/(mol·L·min) 
D)  (mol·L)·min

Question 14

For the reaction 2C → A + B, 0.02 mol of A is formed during the first 15 seconds of the reaction. Assuming that the rate of reaction remains constant for 2 min, which of the following statements is true?

Accepted Answer

A)  After 2 min, 0.16 mol of B was produced. 
B)  After 2 min, 0.16 mol of C was consumed. 
C)  After 2 min, 0.16 mol of B was produced and .16 mol of C was consumed. 
D)  None of these. 
A)  After 2 min, 0.16 mol of B was produced. 
B)  After 2 min, 0.16 mol of C was consumed. 
C)  After 2 min, 0.16 mol of B was produced and .16 mol of C was consumed. 
D)  None of these.

Question 15

Consider the following energy diagram for a reaction.   ​ If a catalyst were added to the reaction represented, which of the following would change position?

Accepted Answer

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

Question 16

Which of the following accounts for the fact that reactions between ions in solution are usually very fast?

Accepted Answer

A)  Ionic bonds are weak. 
B)  No covalent bonds need to be broken for a reaction to occur. 
C)  Reactions between ions are always endothermic. 
D)  Reactions between ions are always exothermic. 
A)  Ionic bonds are weak. 
B)  No covalent bonds need to be broken for a reaction to occur. 
C)  Reactions between ions are always endothermic. 
D)  Reactions between ions are always exothermic.

Question 17

Which of the following is the equilibrium constant expression for the reverse reaction of the following reaction?

Accepted Answer

A)  K = [CH3COOH][C2H5OH]/[CH3COOC2H5][H2O] 
B)  K = [CH3COOC2H5][H2O]/[CH3COOH][C2H5OH] 
C)  K = [CH3COOH][C2H5OH]/[CH3COOC2H5] 
D)  K = [CH3COOC2H5]/[CH3COOH][C2H5OH] 
A)  K = [CH3COOH][C2H5OH]/[CH3COOC2H5][H2O] 
B)  K = [CH3COOC2H5][H2O]/[CH3COOH][C2H5OH] 
C)  K = [CH3COOH][C2H5OH]/[CH3COOC2H5] 
D)  K = [CH3COOC2H5]/[CH3COOH][C2H5OH]

Question 18

Which of the following will not change the numerical value of the equilibrium constant of a particular reaction?

Accepted Answer

A)  increasing the concentration of reactants 
B)  increasing the concentration of products 
C)  increasing the temperature 
D)  increasing the concentration of reactants and increasing the concentration of products 
A)  increasing the concentration of reactants 
B)  increasing the concentration of products 
C)  increasing the temperature 
D)  increasing the concentration of reactants and increasing the concentration of products

Question 19

Drug manufacturers use which of the following when making timed-release drugs?

Accepted Answer

A)  control of the thickness of a drug coating 
B)  control of the size of drugs 
C)  control of the thickness of a drug coating and the size of drugs 
D)  none of these 
A)  control of the thickness of a drug coating 
B)  control of the size of drugs 
C)  control of the thickness of a drug coating and the size of drugs 
D)  none of these

Question 20

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

Accepted Answer

A)  It provides an alternate pathway with a lower activation energy. 
B)  It increases the number of collisions among reacting molecules. 
C)  It makes the reaction more endothermic. 
D)  It makes the reaction more exothermic. 
A)  It provides an alternate pathway with a lower activation energy. 
B)  It increases the number of collisions among reacting molecules. 
C)  It makes the reaction more endothermic. 
D)  It makes the reaction more exothermic.

Exam 7: Reaction Rates and Chemical Equilibrium

What is the effect of increasing the temperature at which a reaction is carried out?

Consider the following energy diagram for a reaction. Which letter represents the activation energy of the reaction?

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

In an energy diagram for an exothermic chemical reaction, which of the following is true?

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

Consider a sample of water in a closed container. When the physical process has reached equilibrium, what can we say about any specific water molecule?

For the exothermic reaction making which of the following changes will ensure that the reaction will not shift either to the left or to the right?

Which of the following is true of most multistep reactions?

To which of the following systems does Le Chatelier's principle apply?

Which of the following best describes the rates of chemical reactions?

In a particular chemical reaction, three bonds are broken and four bonds are formed. Based on this information alone, which of the following is true?

Which of the following is true of effective collisions?

Which of the following units can used to describe the rate of a chemical reaction?

For the reaction 2C → A + B, 0.02 mol of A is formed during the first 15 seconds of the reaction. Assuming that the rate of reaction remains constant for 2 min, which of the following statements is true?

Consider the following energy diagram for a reaction. ​ If a catalyst were added to the reaction represented, which of the following would change position?

Which of the following accounts for the fact that reactions between ions in solution are usually very fast?

Which of the following is the equilibrium constant expression for the reverse reaction of the following reaction?

Which of the following will not change the numerical value of the equilibrium constant of a particular reaction?

Drug manufacturers use which of the following when making timed-release drugs?

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

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

Consider the following energy diagram for a reaction. If a catalyst were added to the reaction represented, which of the following would change position?