Law of multiple proportion Meaning, Definition & Usage

Definitions
  1. (Chem.), the generalization that when the same elements unite in more than one proportion, forming two or more different compounds, the higher proportions of the elements in such compounds are simple multiplies of the lowest proportion, or the proportions are connected by some simple common factor; thus, iron and oxygen unite in the proportions FeO, Fe2O3, Fe3O4, in which compounds, considering the oxygen, 3 and 4 are simple multiplies of 1. Called also the Law of Dalton, from its discoverer.

Webster 1913