Question

Write the name of the following compound and deduce its molecular mass.

NaOH

Answer 1

NaOH - Sodium hydroxide

Molecule	Constituent elements	Atomic mass u	Number of atoms in the molecule	Atomic mass × number of atoms	Mass of the Constituents u
NaOH	Na	23	1	23 × 1	23
	O	16	1	16 × 1	16
	H	1	1	1 × 1	1

The molecular mass of NaOH = Sum of Constituent atomic masses

(Molecular mass of NaOH) = (Atomic mass of Na) × 1 + (Atomic mass of O) × 1 + (Atomic mass of H) × 1

= (23 × 1) + (16 × 1) + (1 × 1)

= 23 + 16 + 1

= 40 u