-
465 BCE
Democritus
Everything in the world is made out of particles surrounded by empty space. The particles varied in size and shape. Came up with the name atomos. (greek meaning indivisible) -
399 BCE
Plato
He thought that matter was composed of indivisible atoms that were in different shapes -
500
The alchemists
They thought all thing were made up of sulfur and mercury in various proportions. 500-1400 AD -
Robert Boyle
He stated that particles can combine to form new substance
(went against alchemy believed at the time) -
Antone Lavoisier
He proved the theory that everything was made out of 4 elements wrong and was the first person to discover elements -
John Dalton
He stated that common substances always broke down into the same elements. He concluded that those elements were made up of atoms which had different sizes and mass and could neither be created or destroyed -
Billiard ball model
This model was created by John Dalton -
Amedeo Avogadro
He stated that equal amounts of gasses all at the same temperature and pressure have the same amounts of molecules -
Dmitri Mendeleev
He created a version of the periodic table and predicted elements that hadn't yet been discovered -
JJ Thompson
He discovered the electron (created the chocolate chip cookie model of the adom) -
Pierre and Marie Curie
They discovered radioactivity, radiation, and two new radioactive elements. -
Plum pudding model
This was created by J. J. Thompson -
Albert Einstein
He predicted the size of atoms using math and proved the existence of them -
Robert Millikan
He discovered the size of the electron (9.10 × 10 to the power of -28 -
Ernest Rutherford
concluded that atoms are made up of mostly empty space with a few electrons while the rest of the atom was in the center which he called the nucleus -
Niels Bohr
He thought electrons orbited the nucleus. He also created the solar system model -
Henry G. J. Mosley
He discovered that the atomic number must equal the amount of protons -
Electron cloud model
this was created by Erwin Schrödinger -
James Chadwich
discovered the neutron -
Erwin Schrödinger
He created the wave equation