What is the gram molecular weight of Sodium hydroxide if its molecular mass is 40 a.m.u?

The a.m.u. is defined as the fraction of 1/12 of an atom of the carbon-12 isotope. The value is pretty nearer to the mass of a hydrogen atom. Therefore, in every compound, the gram molecular weight is numerically equal to the molecular mass in atomic mass units. Therefore the gram molecular weight of NaOH is 40 g/mol.