An evacuated glass vessel weighs 50.0g when empty 148.0 g when filled with a liquid of density $0.98gmL^{-1}$ and 50.5g when filled with an ideal gas at 760mm Hg of 300K.Determine the molecular weight of the gas.

Question

$(a)\;121\qquad(b)\;123\qquad(c)\;221\qquad(d)\;130$