+ equals 23g and 1 mol 28g 3 molecules 3 mol (3 x 2g) = 6g 2 molecules 2 mol H 2 0 7 O.N. Of Cl = : -1 h 2 o O.N. Of O = -2 6.7.6 Exercise - What is it’s concentration in industry, or in solution. • Hard • Dense • Insoluble in polar solvents 8.5.8 Summary: Properties of Electromagnetic Radiation and.