Question

An decrease in the temperature of the reactants causes an decrease in the rate of reaction. The best explanation is: As the temperaturedecreases,

Question 8 options:

1)	the fraction of collisions with total kinetic energy > Ea increases.

2)	the fraction of collisions with total kinetic energy > Ea decreases.

3)	the activation energy increases.

4)	the activation energy decreases.

5)	the concentration of reactants decreases.

Answer 1

Increase or decrease in temperature does not affect the activation energy

so

activation energy neither increases not decreases

also

the temperature has no effect on the conc of the reactants

now

decreasing the temperature causes a fall in the energy levels of the molecules involved in the reaction

As a result lesser number of the reactant molecules will have the activation energy

so lesser molecules will collide and react

finally the rate of the reaction decreases

so

the correct explanation is

As the temperature decreases, the fraction of collisions with total kinetic energy > Ea decreases

so the answer is option 2) the fraction of collisions with total kinetic energy > Ea decreases