0.20 mol of He and 1.00 mol of an unknown compound (vapor pressure 0.70 atm at 300 K) are introduced to an evacuated empty vessel with a movable piston under the external pressure of 1 atm. Considering the ideal gas behavior, determine the total volume of the gases (in L) at 300 K.

Answer

16.42

Explanation

Pressure of He `=1- 0.70 = 0.30` atm
`V = (nRT)/P = (0.20 x 0.0821 xx 300)/0.30 = 16.42` L