Question : 9.1 Multiple Choice Questions 1) A catalyst A) a reactant in : 1362952

9.1

Multiple Choice Questions

1) A catalyst is

A) a reactant in a chemical reaction.

B) a product in a chemical reaction.

C) a substance that speeds up a reaction without being consumed in the reaction.

D) a substance that increases the energy of the products.

E) a substance that decreases the energy of the products.

2) When a reaction is at equilibrium,

A) all reaction stops.

B) no more reactants are converted to products.

C) the reaction is no longer reversible.

D) the forward and reverse reactions occur at the same rate.

E) the products and reactants have the same energy content.

3) For the following equilibrium reaction, which cause and effect are correctly matched?

CO(g) + 2H2 (g) ? CH3OH(g) + heat

A) add heat, shift right

B) add CO, shift left

C) remove CH3OH, shift left

D) remove heat, no change

E) remove H2, shift left

4) The activation energy of a chemical reaction is the energy that

A) must be removed from the mixture.

B) must be released from the mixture.

C) initiates the reaction.

D) activates the catalyst.

E) is the difference in the energies of the starting materials and products.

5) A chemical reaction has reached equilibrium when

A) the concentrations of reactants and products are equal.

B) all reactants have been converted to products.

C) all products have been removed from the reaction mixture.

D) the catalyst has been used up.

E) the rate of the forward reaction equals the rate of the reverse reaction.

6) In a catalyzed chemical reaction, one function of a catalyst is to

A) increase the number of successful reactant collisions.

B) decrease the concentration of reactants.

C) change the equilibrium concentrations of the products and reactants.

D) increase the energy given off during the reaction.

E) increase the temperature at which the reaction is carried out.

7) In the following gas phase reaction, what is the effect of adding more NO2 to the starting reaction mixture?

2NO2 ? N2O4

A) It would make the reaction more endothermic.

B) It would make the reaction more exothermic.

C) It would slow the reaction down.

D) It would decrease the final quantity of products.

E) It would increase the final quantity of products.

8) The physiological equilibrium system that keeps the temperature of the body constant is called __________.

A) stimulation

B) regulation

C) metabolism

D) homeostasis

E) catalysis

9) When you open a bottle of a soft drink and leave it open, the drink eventually goes flat. This happens because the equilibrium between carbonic acid and carbon dioxide shifts to produce

A) more carbonic acid.

B) more water.

C) more oxygen.

D) more carbon dioxide.

E) more hydrogen ions.

10) Iron metal reacts with oxygen gas to produce iron(III) oxide. What will be the effect of increasing the pressure of oxygen gas in a closed reaction vessel?

A) Less reaction will take place.

B) More iron oxide will be produced.

C) The reaction mixture will catch fire.

D) There is no effect; a catalyst is needed.

E) The rate of production of iron oxide will slow down.

1