The sulphate of a metal `M` contains `9.87%` of `M`. This sulphate is isomorphous with `ZnSO_4.7H_2O`. The atomic mass of `M` is :

Options

A. 12
B. 24
C. 36
D. 48

Answer

B

Explanation

Equivalent of metal sulphate = Equivalent of metal
`rArr ("Wt of metal sulphate")/("Eq. wt. of metal sulphate") = ("Wt. of metal")/("Eq. wt. of metal") rArr (W_("metal sulphate"))/(E_(M) + E_("Sulphate"))`
`rArr (W_("Metal sulphate"))/(W_(M)) = (E_(M) + 48)/(E_(M)) rArr (100)/(20) = (E_(M) + 48)/(E_(M)) :. E_(M) = 12`