Question

molar mass of Cl atoms and Cl molecules

Answer 1

There is no molar mass of cl atom is 35.5 ..... the molar mass of molecule(Cl) is there i.e. 70.9

Answer 2

molar mass of Cl is 35.45 g/mol
Cl2 molecule molar mass = 35.45 + 35.45 = 70.9 g/mol