Chapter 5. Chemical Kinetics

Question 1

The rate of reaction that does not involve gases is not dependent on:

a. temperature
b. catalyst
c. concentration
d. pressure

Answer 1

d. pressure

Question 2

For an effective collision to take place, there must be:

a. no products present
b. high pressure and temperature
c. a correctly oriented collision
d. a sufficiently hard collision

Answer 2

c. a correctly oriented collision

Question 3

In the reaction 2B → product. if the concentration of ‘B’ is doubled, the rate of reaction will increase by?

Answer 3

four (4) times

Question 4

Powdered marble reacts more rapidly with HCl than the chips of marble because:

a. number of molecules increases
b. surface area of powdered marble is more than that of chips of marble and hence there is more collisions between the molecules of reactants.
c. energy of activation increases
d. energy of activation decreases

Answer 4

b. surface area of powdered marble is more than that of chips of marble and hence there is more collisions between the molecules of reactants.

Question 5

The rate of a reaction increases with the increase of concentration of reactants because?

a. number of collisions per unit time between the reacting molecules increase due to increase in number of molecules of reactants
b. number of molecules per unit volume increases
c. the activation energy is lowered down
d. the enthalpy change for the reaction decreases

Answer 5

a. number of collisions per unit time between the reacting molecules increase due to increase in number of molecules of reactants

Question 6

The rate of chemical reaction depends on the nature of reactants because

a. all are correct
b. some of the reactants are colored
c. some of the reactants are solid at room temperature
d. energy of activation differ from one reactant to another

Answer 6

d. energy of activation differ from one reactant to another

Question 7

Dust particles suspended in the air inside unheated grain elevators can sometimes react explosively because the dust particles have a:

a. high activation energy
b. catalytic effect on the reaction
c. high kinetic energy
d. large surface area of the reaction

Answer 7

d. large surface area of the reaction

Question 8

The concentration of the reactant/reactant in determining the rate of reaction is expressed as:

Answer 8

moles per liter (mol/L)