-
400
Democritus
He theorized that atoms were specific to the material which they were composed. Also believed that atoms come in different size and shape. -
428
Plato
He made the five solid shapes whose sides are made of regular polygons and thought that atoms of matter must be one of these five solid shapes. -
500
The Alchemists
they found the 4 basic elements fire, earth, wind, and water and created the foundation of the modern day periodic table. -
Robert Boyle
He believed that all substances were made up of atoms and also called them the particles of the atom. -
Antone Lavoissier
He found out that the products and reactants in a chemical reaction are always the same after the change. -
Amedeo Avogadro
He made the Avogadro law and was the first to say that elements could exist in the form of molecules -
John Dalton
He proposed the that all matter was composed of atoms, indivisible and indestructible building blocks. Atoms also have differing size and mass. -
Dmitri Mendeleev
Devised the periodic classification of the chemical elements. elements were classified as there weights of the atoms. -
JJ Thompson
He showed that all atoms contain tiny negatively charged subatomic particles or electrons. Positively charged "soup". -
Pierre and Marie Curie
They both discovered the elements Radium and Polonium. Also, When they discovered these elements, they were testing radioactivicty at the same time. -
Albert Einstein
He mathmatically proved that atoms existed and helped revolutionize all sciences through statistics. -
Robert Millikan
He determined the change of the electron with small electrical charged drops of oil. -
Ernest Rutherford
Found that atoms consist mostly of empty space, with it's mass concentrated in the center of the positive nucleus -
Neils Bohr
Says that electrons move around a nucleus, but only in prescribed orbits. Also, if electrons move to a lower level, it changes the elements identity. -
Henry G. J. Mosely
Proved that every element's identity is uniquely determined by the number of protons. revealed the true basis of the periodic table. -
Erwin Schrodinger
He used bohr's model to use mathmatical equations to describe a electron in the center of a Atom/Nucleus is impossible. -
Werner heisenberg
He discovered that electrons don't go around or inside of the Nucleus. -
James Chadwich
He discovered the neutron inside the atom. He says that the neutron has no charge that makes the atoms nucleus.
