The half-life of a reaction is inversely proportional to the square of the initial concentration of the reactant. Then the order of the reaction is

Options

(a) 0
(b) 1
(c) 2
(d) 3

Correct Answer:

3

Explanation:

t(1/2) = ∝ 1 / a² .

We know that t(1/2) ∝ 1/ a (n-1),

⇒ a² = a (n-1) or n -1 = 2 ⇒ n = 3.

Thus reaction is of third order.