Question

Which is the unit of rate constant for the first-order reaction if time is expressed in seconds?

Options

• mol^-1 dm³ s^-1

• s^-1

• mol dm^-3 s^-1

• mol dm^-3 s

Answer 1

s^-1 

Explanation:

For first order reaction

k = `2.303/"t" log ["a"/("a - x")]`

The units ofrate constant is time^-1 = sec^-1 i.e., s^-1