Law Of Definite Proportions Law Of Constant Composition
What is Law Of Definite Proportions Law Of Constant Composition?
The law of definite proportions (law of constant composition) states that a given chemical compound always contains the same elements in the same fixed ratio by mass, regardless of the source or method of preparation. For example, water always consists of 11.19% hydrogen and 88.81% oxygen by mass. This law, formulated by Joseph Proust in 1797, was one of the cornerstones of Dalton's atomic theory and distinguishes pure compounds from mixtures.
Key Facts
Frequently Asked Questions
The law of definite proportions (law of constant composition) states that a given chemical compound always contains the same elements in the same fixed ratio by mass, regardless of the source or method of preparation. For example, water always consists of 11.19% hydrogen and 88.81% oxygen by mass. This law, formulated by Joseph Proust in 1797, was one of the cornerstones of Dalton's atomic theory and distinguishes pure compounds from mixtures.