A vessel containing 1gm of oxygen at a pressure of 10atm a temperature of $47^{\large\circ}C$.It is found that because of a leak,the pressure drops to $\large\frac{5}{8}$th of its original value & temperature falls to 2x.Find the mass of oxygen that has leaked out.

Question

$\begin{array}{1 1}(A)\;\large\frac{1}{3}\\(B)\;\large\frac{2}{3}\\(C)\;\large\frac{3}{5}\\(D)\;\large\frac{2}{5}\end{array}$