Atomic theory
Dalton's Atomic Theory :- The atomic theory of matter was first proposed on a firm scientific basis by John Dalton, a British school teacher in 1808.His theory called Dalton's atomic theory regarded the atom as the ultimate particle of matter In 1808,Dalton published 'A New System of chemical Philosophy ' in which he proposed the following :- (a) Matter consists of indivisible atoms. (b) All the atoms of a given element have identical properties including identical mass. Atoms of different elements differ in mass. (c) Compounds are formed when atom of different elements combine in a fixed ratio. (d) Chemical reactions involve reorganisation of atoms. These are neither created nor destroyed in a chemical reaction . The major problems before the scientists at that time were :- 1.To account for the stability of atom after the discovery of sub-atomic particles. 2.To compare the behaviors of one element from other in terms of both physical and ...