law of definite proportions
A chemistry teacher draws a diagram of water molecules on the board to illustrate the law of definite proportions.
Noun: - A fundamental chemical law: The law of definite proportions states that a given chemical compound always contains its component elements in fixed and constant proportions by mass, regardless of its source or method of preparation.
This term is used in the context of chemistry to describe a foundational principle of chemical composition. - The law of definite proportions is a cornerstone of modern chemistry. - Water always obeys the law of definite proportions, consisting of hydrogen and oxygen in a fixed mass ratio.
- Also known as: Proust's Law, named after the French chemist Joseph Louis Proust who formulated it.
- Proust's Law, or the law of definite proportions, was crucial in developing atomic theory.
- Law of multiple proportions (n): A related chemical law stating that when two elements form more than one compound, the ratios of the masses of the second element that combine with a fixed mass of the first element are ratios of small whole numbers.
- Proust's Law: The historical name for the same principle.
A chemistry teacher draws a diagram of water molecules on the board to illustrate the law of definite proportions.
- (chemistry) law stating that every pure substance always contains the same elements combined in the same proportions by weight