NEET Solved Paper 2018 Question 34

Question: The correct difference between first and second order reactions is that [NEET - 2018]

Options:

A) A first-order reaction can catalyzed; a second-order reaction cannot be catalyzed

B) The half-life of a first-order reaction does not depend on $ {{[\text{ A }]}_0} $ ; the half-life of a second-order reaction does depend on $ {{[\text{ A }]}_0} $

C) The rate of a first-order reaction does not depend on reactant concentrations; the rate of a second-order reaction does depend on reactant concentrations

D) The rate of a first-order reaction does depend on reactant concentrations; the rate of a second-order reaction does not depend on reactant concentrations.

Show Answer

Answer:

Correct Answer: B

Solution:

  • For first order reaction, $ {{t} _{1/2}}=\frac{0.693}{k} $ , which is independent of initial concentration of reactant. For second order reaction, $ {{t} _{1/2}}=\frac{1}{k[A _0]} $ , which depends on initial concentration of reactant.