Chemical Kinetics

The rate of the reaction, \(\mathrm{CH}_3 \mathrm{COOC}_2 \mathrm{H}_5+\mathrm{NaOH} \longrightarrow \mathrm{CH}_3 \mathrm{COONa}+\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}\) is given by the equation, rate \(=k\left[\mathrm{CH}_3 \mathrm{COOC}_2 \mathrm{H}_5\right][\mathrm{NaOH}]\). If concentration is expressed in \(\mathrm{mol} \mathrm{L}^{-1}\), the unit of \(k\) is