$PC{l}_{5\left(g\right)}$ decomposes at temperature T K in to $PC{l}_{3\left(g\right)}$ and $C{l}_{2\left(g\right)}$ according to 1st order kinetics. In a closed container initially only $PC{l}_{5\left(g\right)}$ was taken at 2atm & T K. After 12 seconds the pressure in container found to be 2.4 atm at same temperature. The rate constant (in min-1) for the decomposition of $PC{l}_{5\left(g\right)}$ at T K is _______$(\mathcal{l}n10=2.3,\mathcal{l}n2=0.7)$