Dalton's atomic theory had several parts to it. He believed atoms were indivisible, or impossible to break down into smaller particles. Also, he said elements are all consisted of atoms and that the atoms of each element are different from each other. All of the atoms of the same element are identical, but different from atoms of other elements. According to Dalton's theory, these different elements can be chemically merged or physically mixed to make compounds. Also, when forming chemically combined compounds with chemical reactions, atoms cannot be created or destroyed.
Earnest Rutherford preformed en experiment later that proved an idea of Dalton's wrong. With his gold foil experiment, Rutherford found atoms to be consisted of at least two smaller parts, unlike Dalton's idea that atoms are indivisible. He established that an atom includes a tiny, positively charge nucleus, which is surrounded by electrons.
Both John Dalton and Ernest Rutherford, among other great researchers and scientists, assisted in creating the atomic theory that exists today. Dalton's theory was the first modern atomic theory, but a part of it was disproven by Rutherford. Rutherford found atoms were not indivisible and that they consist of smaller parts and particles. Even though one of Dalton's ideas was proved wrong, his other thoughts still apply to today's atomic theory.