Question

Which of the following statements is true? a) The rate constant does not depend on the activation energy for a reaction where the products are lower than the reactants. b) A catalyst raises the activation energy of a reaction. c) Rate constants are temperature dependent.

Answer 1

Answer:

Rate constants are temperature dependent.

Explanation:

Reaction rate is used to quantify the rate of chemical reaction. There is a relationship between the reaction rate and the half-life of the reaction and the Gibbs free energy of activation, and the reaction rate is temperature dependent according to the equation.

For a reaction shown below

a A + b B ⇒ c C

The rate of reaction of the reaction is given by

$r = k(T) [A]^{m}[B]^{n}$

where k(T) is the reaction constant, which is seen to be dependent on the temperature of the reaction.

Also, k(T) is numerically equal to

$k(T) = Ae^{\frac{E_{a} }{RT} }$

where

r = reaction rate

A = pre exponential factor

$E_{a}$ = Activation energy

R = gas constant

T = temperature

and m and n are experimentally determined partial orders in [A] and [B]