What weight of each element is present in 1.5 moles of sodium sulphite, Na2SO3?
(Atomic masses: Na = 23 u; S = 32 u; O = 16 u)
1.5 moles of Na2SO3 has 1.5×2 = 3 moles of Na
1.5 moles of Na2SO3 has 1.5×1 = 1.5 mole of S
1.5 moles of Na2SO3 has 1.5×3 = 4.5 moles of O.
As we know that Mass of an element= number of moles x atomic mass
Thus, mass of sodium = 3 × 23 g = 69g
Mass of sulphur = 1.5 × 32 = 48g
Mass of oxygen = 4.5 × 16 g = 72g