The law of definite proportion : A chemical compound eternally
holds exactly the same proportion of elements by mass. This sometime also called Proust's Law.
This law tells us that a chemical compound that is pure always consists of the same elements combined together in a fixed proportion by weight.
This law was proposed by Joseph Proust.
Let us understand this law with the help of an example.
Case 1: Burning Coke In Air: C(s) + O2(g) --Heat---> CO2(g). In this reaction we combine coke which is an allotrope of carbon with oxygen. To form Carbon Dioxide.
By the decomposition of Limestone in Air: Lets see the chemical reaction. CaCO3 ----heat--> CaO(s) + CO2(g) Calcium carbonate on decomposition reaction will give calcium oxide and carbon dioxide.
