First, C2F3Cl3 has a molar mass of 187.38 g/mole. So there are 117.41 moles of this compound. By ratio, then there are 352.23 moles of chlorine. Chlorine has a molar mass of 35.453 g/mole, so there are 12.488 kg of chlorine in that compound. CF3Cl has a molar mass of 104.46 g/mol = 210.61 moles. By ratio, there are an equivalent number of moles of chlorine, so there is 7.467 kg of chlorine in the second compound.