What are the different laws of chemical combination ? We study the different aspects of chemical reactions in the various chemical combinations.
Law of conservation of mass : Laws of chemical combination
In all physical and chemical changes, total mass of the system remains constant. It means matter is neither created nor destroyed.
Physical changes in Laws of conservation of mass : Laws of chemical combination
The mass of reactant becomes equal to the mass of the products. For example: heat a cube of ice in a well corked flask. The mass of ice and water remains same before and after the reaction.
Chemical changes in Laws of conservation of mass
Observe the precipitation reactions. NaCl + AgNO3 ➡️ NaNO3 + AgCl. Here, total mass of the system remains constant.
Take the example of decomposition reaction. Matter remains same before and after the reaction.
The Law of constant composition or definite proportion : Laws of chemical combination
A chemical compound is made up of same elements in a fixed ratio by mass. For example: H2O always consists of H and O elements in the ratio of 1 : 8 ( mass )
Law of multiple proportions : Laws of chemical combination
Consider the example of 2 elements combine to form 2 or more compounds. The mass of E1 combines with the fixed mass of E2 in a simple whole number ratio.
Law of reciprocal proportion : Laws of chemical combination
2 elements A and B combines with the fixed mass of 3rd element is same or in simple whole number ratio.
Law of Gaseous volumes
Gases react together in volumes, bears a simple ratio to one another and to the volume of gaseous products. For example : 2H2 ( 2 vol ) + O2 (1 vol) ➡️ H2O (2 Vol ). Therefore, the ratio of volume of reactants to products 2 : 1 : 2
Check out the structure of NH3 here
For more updates join me on
You Tube Channel Chemistry with mona mam
Website Basics of chemistry.com
