-
360
aristotle
came up with the idea that things are made up of small things -
400
Democrates
concluded that, because you cannot cut an item in half forever, there must be something there too small to see. he named it the "atomos." -
John dalton
Found out that all matter is made up of atoms. Atoms are indivisible and indestructable.
All atoms of a given element are identical in mass and properties
Compounds are formed by a combination of two or more differnet kinds of atoms
A chemical reaction is a rearrangement of atoms
atoms are neither created nor destroyed. also came up with the billard ball as the idea of the structure of the atom -
Henri Beqerel
became the first scientist to discover radioactivity -
JJ Thomson
Discovered electron
theory: discovered that the atom consists of positive charge with tnegatively charged electrons embedded in it.
the positive and negative charges are =. therefore an atom's charge is neutral. -
Marie and Pierre Curie
Credited with discovering the elements radium and polonium. -
Enist Rutherford
Credited with Discovering Alpa rays- positive, Beta rays- negative, and gamma rays- neutal -
Max Plank
Discovered and created the quantum theory based on the idea that all atoms lost their energy over time -
Ernest Rutherford
Discovered that the atom had a nucleus, rather than just a ball. with a positive core, and a flow of negative electons. Discovered most of the mass is in the nucleus. -
Robert milikan
Proved Thomson's theory that the electron is 100x samller than the nucleus -
Niels Bohr
Created the Bohr's model. Planetary in shape. Deduced that the electrons have a constant movement at a stationary orbit. -
Werner Karl Heisenberg
Credited with being one of the key makers of Quantum Mechaics -
Erwin Shrodinger
discovered that the atom is more cloud-like than "planetary" -
Chadwick
Famed for the discovery of the Neutrally Charged "Neutron" within the atom -
Henery Mosely
Credited with the creation of the modern periodic table
