134) 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.
135) 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.
136) 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.
Indicate the effect of each change (#138) upon the rate of a reaction (increases, A or decreases,
B).
137) adding a catalyst
138) removing some reactant
139) the temperature is doubled.
140) The concentration of a reactant is decreased.
141) More collisions between molecules occur.
Chapter 10: Acids and Bases
142) According to the Arrhenius concept, if NaOH were dissolved in water, it would act as
A) a base.
B) an acid.
C) a source of hydronium ions.
D) a source of H
-
ions.
E) a proton donor.
143) According to the Arrhenius concept, if HNO
3
were dissolved in water, it would act as
A) a base.
B) an acid.
C) a source of hydroxide ions.
D) a source of H
-
ions.
E) a proton acceptor.
144) The name given to an aqueous solution of HBr is
A) hydrogen bromide.
B) hydrobromic acid.
C) bromic acid.