Question

In the estimation of sulphur by carius method, 0.480 g of an organic compound gives 0.699 g of barium sulphate. The percentage of sulphur in this compound is: (atomic masses : ba = 137, s = 32 and o = 16)

Answer 1

Hi....

The mass of organic compound taken = 0.468g

mass of BaSO4 formed = 0.668g

we know,

atomic mass of sulphur = 32g/mol

molecular mass of BaSO4 = 233 g/mol

Applying the relation,

Percentage of sulphur = (32/233) × {mass of BaSO4 formed/mass of organic substance taken } × 100

= (32/233) × {0.668/0.468}×100

= 3200× 668/(233 ×468)

= 19.60 %

Hence, percentage of sulphur in the given compound is 19.6%

Hope it helps....