-
440 BCE
Plato
Proposed that ideal genometric forma serve as atoms -
400 BCE
Democritus
He proposed that atoms are indestructible -
Robert boyle
The volume of gas inversely proportional to pressure exerted by the gas -
Antoine Lavoisier
Defining the law of conservation of mass -
The Alchemists
demonstrated that the atoms in radioactive materials disintegrate, so that the atoms of a radioactive element are transformed into another element -
John Dalton
He came up with the first atomic theory of all matter is made of atoms, that you cant see -
Solid sphere
-
Dmitri Mendeleev
Made the periodic table based of atomic weight and number -
J.J Thompsen
All atoms contain tiny negatively changed particles or electrons. -
The curies
Discovered the isolation of radium, which provided science with a method for isolating and purifying radioactive isotopes. -
Plum pudding Model
-
Albert Einstein
mathematically proved the existence of an atom. -
Robert Millikan
Falling drop method proved that quality was constant for all electrons and precisely determining the magnitude of the electron's charge -
Ernest rutherford
Postulated the nuclear stuckture of the atom discoved alpha and beta rays and proposed the laws of radioactive decay -
Solar system model
-
Henry G.J. Mosely
The frequencies are proportional to the squares of whole numbers are equal to the atomic number plus a constant. -
Niel bohr
Work on structure of atoms and he created the Bohr model, the most widely accepted model of the atom. -
electron cloud model