Irene Villanueva Famous Dead Guy By ivill83 101 Thales (624-546 B.C.) Thought all things were made of water 101 Democritus (460 B.C.) First person to think of the atom. Thought it was a solid sphere. 101 Aristotle (384 B.C-322 B.C) All substance were made of fire, water, earth, and air. Oct 7, 1702 Isaac Newton Matter is formed of solid, massy impenetrable particles. Oct 7, 1802 John Dalton Atomic theory all matter is made of atoms atoms are indivisible and indestructible All atoms of a given element are identical in mass and properties compounds are formed by a combination o ftwo or more different kinds of atoms A chemical reaction is a rearrangement of atoms He was the first person to have experimental evidence. Oct 7, 1896 Henri Becquerel Discovered radioactivity and thought the atoms was a sphere. Oct 7, 1897 Joseph John Thomson He is widely recognized for his discover of the electron. His model had negative charge in the atoms. Oct 7, 1909 Ernest Rutherford He discovered the nucleus. Oct 7, 1912 Millikan (1909-1912) Found the charge of an electron. Oct 7, 1916 Niels Bohr (1911-1916) created the Bohr model of the atom thought that electrons orbited around the nucleus Oct 7, 1926 Erwin Schrodinger the quantum mechanical model predicts the odds of electron location proved Bohr model wrong Oct 7, 1932 James Chadwick Proved the existence of neutrons.