law of definite proportions การใช้

There are, however, exceptions to the Law of Definite Proportions.
The law of definite proportions might seem obvious to the modern chemist, inherent in the very definition of a chemical compound.
Berthollet was engaged in a long-term battle with another French chemist Joseph Proust on the validity of the law of definite proportions.
But it was found later that Berthollet was not completely wrong because there exists a class of compounds that do not obey the law of definite proportions.
;1797 : Joseph Proust proposes the law of definite proportions, which states that elements always combine in small, whole number ratios to form compounds.