For the first order thermal decomposition reaction, following data was obtained : $\text{C}_2\text{H}_5\text{Cl(g)} \longrightarrow \text{C}_2\text{H}_4\text{(g)} + \text{HCl(g)}$ | S. No. | Time(s) | Total Pressure (atm) | | :---: | :---: | :---: | | 1 | 0 | 0.30 | | 2 | 30 | 0.50 | Calculate rate constant. $\quad \quad \quad \quad \quad \quad \quad \quad \quad \quad \quad \quad \quad$ [Given : $\log 3 = 0.48$]