The following data were obtained during the first order thermal decomposition of $\text{C}_2\text{H}_5\text{Cl}$ at a constant volume : $\text{C}_2\text{H}_5\text{Cl (g)} \longrightarrow \text{C}_2\text{H}_4 \text{(g)} + \text{HCl (g)}$ | Experiment | Time $(\text{s}^{-1})$ | Total pressure (atm) | | :--- | :--- | :--- | | 1 | 0 | $0\cdot4$ | | 2 | 100 | $0\cdot6$ | Calculate the rate constant. (Given : $\log 2 = 0\cdot3010, \log 3 = 0\cdot4771, \log 4 = 0\cdot6021$)