law of definite 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 law

See 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