Question

An organic compound having `C,H` and sulphur contains `4%` of sulphur. The minimum molecular weight of compound is
A. 200
B. 400
C. 600
D. 800

Answer 1

Correct Answer - D
`%` of `S = ("wt. of 1 sulphur atom")/(" Minimum mol. Wt.") xx 100`
`4 = (32)/(" Minimum mol.wt.") xx 100`
Minimum mol. Wt =` 800 g mol^(-1)`
(a) , (b) and (c ) are not possible.
Alternate Method: A compound must have at leat one atom of S i.e, `32g` of S.
4g of sulphur is present in 100 g of compound.
`32g` of sulphur will be present in `(100)/(4) xx 32 = 800 g mol^(-1)`.