A 2.85 g sample of an unknown chlorofluorocarbon is decomposed and produces 558 mL of chlorine gas at a pressure of 756 mmHg and a temperature of 298 K.What is the percent chlorine (by mass) in the unknown chlorofluorocarbon?

1 answer

Use PV = nRT and solve for n = number of moles Cl2.
Convert moles Cl2 to g Cl2.
%Cl = (mass chlorine/2.85)*100 = ??