Question

How can the law of definite proportions be used to differentiate between compounds?

Answer 1

Tell me the ratio of `N:O` in the following nitrogen oxides: `NO`; `NO_2`; `N_2O_5`?

Explanation:

All of these nitrogen oxides are real species, but manifestly have different elemental proportions. Of course, the law cannot be used to differentiate the radical `NO_2`, from `N_2O_4`. Why not?