Evolution of the modern atomic theory?

Question

How the modern atomic theory changed sinced atoms were discovered?

Answer 1

Early atomic theories consisted mainly of beliefs that there were a few types of fundamental elements (such as earth, fire, water, and air) that made up all substances. Modern atomic theory came about in 1803, when John Dalton theorized that each chemical element was composed of a unique type of atom. Dalton believed that compunds always formed from one-to-one ratios of elemental atoms, but Amedeo Avogadro showed in 1811 that this is not the case, and that some elments exist in molecular form. Prior to 1897, the atom was believed to be undividable. But in that year, J.J. Thomson discovered the electron. However, he believed that they were embedded in a positively charged mass (the "plum pudding model") in order to account for the overall neutrality of atoms. In 1909, Thomson's student Ernest Rutherford showed that the atom actually contains a concentrated, positive charge at its center, the nucleus. It was believed that the elctrons orbited the nucleus (the "planetary model"). Eventually, during the 20th century, this was replaced by quantum mechanical models of the atom, where electrons occupy "orbitals" that are actually probability distributions of where electrons may be found.

Answer 2

No one can answer this question. When two hydrogen atom fuses to give helium. Thats all i know. How proton and electron evolved. Sorry i don't know. On behalf of you, i'll ask this question in Physics category.