Question

The plot of $t_{1/2}v/s[R{]}_0$ for a reaction is a straight-line parallel to x-axis. The unit for the rate constant of this reaction is:

• A. $mol{L}^{-1}s$
• B. $mol{L}^{-1}{s}^{-1}$
• C. $Lmo{l}^{-1}{s}^{-1}$
• D. $s^{-1}$

Answer 1

The correct option is D $s^{-1}$

There is no change in the half-life as the initial concentration changes. This means that the half-life is independent of the concentration, which happens only in a first order reaction. Here, the rate = k[A], hence k has the unit of $s^{-1}$.