……………………… reaction obeys the expresison `t_(1//2) = 1//ka` in chemical kinetics.

Options

A. first
B. second
C. third
D. fourth

Answer

B

Explanation

`T_(1//2)` for nth order reaction `= (2^(n-1) - 1)/((n-1)k(a)^(n-1))`
On subsitituting `n = 2`, we obtain
`T_(1//2) = (2-1)/(1.k.a) = (1)/(k a)`
Therefore, the order of the reaction is `2`.