Two oxides of a metal contain `27.6%` and `30.0%` of Oxygen, respecttively. If the formula of the first be `M_(3) O_(4)`. Find that of the second.

Answer

`M_(2)O_(3)`

Explanation

Suppose, the atomic weight of the metal is x. The oxide A has the molecular formula `M_3O_4`. The molecular mass of `A = 3x + 64.0`
Hence, the percentage of oxygen in A `=64/(3x + 64) xx 100`
According to the given data, A contains 27.60 % oxygen
`therefore 64/(3x + 64) x 100 = 27.60` or `x = 55.96`
Thus, the atomic weight of the metal M is 55.96. Formula of the oxide B can be obtained as follows :

Hence, the formula of oxide B `=M_(2)O_(3)`.