Question

7. Calculate the mass per cent of different elements present in sodium sulphate
(Na2 SO4.).Atomic mass of Na,S and O are 23,32 and 16 respectively.​

Answer 1

Molar mass of Na

2

SO

4

= 23×2+32+4×16=142

Na=

142

23×2

×100=32.4%

S=

142

32

×100=22.5%

O=

142

64

×100=45%