-
460
Democritus
460 BC-370 BC
Believed matter was made up of atoms which he said where physically indivisble, has space between them but always stayed in motion. -
Antoine LAvoisier
1743-1794
He proved the law of conservation -
Joseph Proust
1754-1826
He was known for proving that every pure compont consists of elements in a definite proportion -
John Dalton
1766-1844
saId that chemical reactions can be explained by the union and separation of atoms, and that these atoms have characteristic properties. have five assuptions to his theory -
Heneri Becquerel
1852-1908
while doing an experiment of the exposure of a uranium bearing ccrytal to sunlight; he discovered radioactivity. -
Masrie and Pierre Curie
was interested in Henri becquerel experimenttts and end up finding two new radioactive elements -
JJ Thomson
was able to measure the rays of cathode rays at which they were deflected, and then caculated the ratio of the electrical charge tot the mass of the particles. -
Ernest Rutherford
found that atoms are mainly made up of empty space. became known as the father of nuclear physics -
robert millikan
measured the charge of an electron -
James Chadwick
He discovered the neutron
