If the masses of `Mn` of `O` are in the ratio of `55 : 16` in `MnO`, what is the ratio of `O` that combines with the same mass of `Mn` in `MnO_(2)` and `Mn_(2) O_(7)` ?

Explanation

In `MnO_(2)`, 1 atom of `Mn` combines with 1 atom of `O (16)`. Therefore,in `MnO_(2)`, 1 atom of `Mn` will combine with 7 atoms or `7 xx 16 = 112` parts of `O` in `Mn_(2)O_(7)`. Hence, 1 atom of `Mn` will combine with `112//2 = 56` parts of oxygen. The ratio of `O` that combines with the same mass of `Mn` is `MnO_(2) : Mn_(2)O_(7) : : 32 : 56`, i.e., `4 : 7`.