law of definite proportions
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Related to Law of constant composition: law of definite proportions, law of multiple proportions
law of def·i·nite pro·por·tions
the relative weights of the several elements forming a chemical compound are invariable.
Synonym(s): Proust law
law of definite proportions
Two or more elements when united to form a new substance do so in a constant and fixed proportion by weight.
See: Dalton's lawSee also: law
Proust,
Louis J., French chemist, 1755-1826.Proust law - the relative weights of the several elements forming a chemical compound are invariable. Synonym(s): law of definite proportions