Write about Dalton's Atomic Theory.

(N/A) The first atomic theory was proposed by John Dalton in $1808$.
According to this theory:
$(i)$ Matter consists of indivisible atoms.
$(ii)$ All atoms of a given element have identical properties,including identical mass. Atoms of different elements differ in mass.
$(iii)$ Compounds are formed when atoms of different elements combine in a fixed ratio.
$(iv)$ Chemical reactions involve the reorganization of atoms. Atoms are neither created nor destroyed in a chemical reaction.