law of definite proportions: Quick Facts

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Facts

Also Known As	law of constant composition • Proust’s law

Topics

equivalent weight law of reciprocal proportions law of multiple proportions stoichiometry chemical compound chemical bonding chemical analysis coordination compound acid–base reaction organic compound reaction mechanism dye organometallic compound catalysis chemical reaction

Key People

John Dalton

John Dalton

British scientist

Joseph-Louis Proust, medallion by Pierre-Jean David

Joseph-Louis Proust

French chemist

Double exposure of science laboratory test tubes with bokeh and chemical reaction

Types of Chemical Reactions