LAWS OF CHEMICAL COMBINATION There are four laws of chemical combination which describe the general features of a chemical change. Although research has shown that these laws are only approximately correct, they still form the basis of chemistry. The Law of Conservation of Mass The Atomic Theory proposed by John Dalton states that atoms can neither be created nor destroyed but change from one form to another. Since matter is made up of atoms, matter too can neither be created nor destroyed. This is stated in the Law of Conservation of