Question

State two laws of chemical combination.

Answer 1

the two laws are matter can neither be created and nor be destroyed .or in other words the total mass that is the sum of mass of reacting mixture and the products formed remain constant .

Answer 2

1. Law of Conservation of Mass

In simple terms, this law states that matter can neither be created nor destroyed. In other words, the total mass, that is, the sum of mass of reacting mixture and the products formed remains  constant. Antoine Lavoisier gave this law in the year 1789 based on the data he obtained after carefully studying numerous combustion reactions.

2. Law of Definite Proportions

Joseph Proust, a French chemist stated that the proportion of elements by weight in a given compound will always remain exactly the same. In simple terms we can say that, irrespective of its source, origin or its quantity, the percent composition of elements by weight in a given compound will always remain the same.

Hope this will help you ^_^