Hisytory Of The Atom by Harshita Pachigolla

Aristole

384

Aristotle was a teacher at his school he called Lyceum. He was influence by books, but he was really dedicated to science. He stated that all sibstances were made from the 4 elements:
Earth
Wind
Fire
Water
He later then escaped to Macedonia for about a year to continue his study of Biology.

Democritus

460

Democritus
22 Jan 460 Democrtitus was born in Greek and he discovered the atom. He oducted an experient where he broke apart a seashell until a powder was only left. He then tried to break the tiniest piece of the powder and he didn't succeed. Therefore, he decided to name it atom, which in greek means "invisible."

Jhon Dalton

Jan 22, 1800

John Dalton
22 Jan 1800 John Dalton transformed Democritus' ideas on atoms into a scientific theory. He stated that all matter is made up of tiny particles that we call atoms and that the atoms from divergent elements would combine in small numerical ratios to form chemical compounds.

J.J thompson

Jan 22, 1897

J.J Thomson
22 Jan 1897 J.J Thomson discovered the elctron while conducting the Cathode Ray experiment. By adding a cathode ray rube he ascertained that all of the moving pieces were electrons.

Robert Millikan

Jan 22, 1909

Robert Millikan
22 Jan 1909 Robert Millikan determined the mass and charge of the of the elctron. He conducted the oil drop experiment and found that the mass from the drop of the oil, he calculated the charge on an electron.

Ernest Ruthford

Jan 22, 1912

Ernest Ruthford
22 Jan 1912 Ernest Ruthford was born in New Zealand. He discovered the nucleus when he conducted the goldfoil experiment. He made a hypothesis and model of his results.

Niels Bohr

Jan 22, 1913

Neils Bohr
22 Jan 1913 Neils Bohr was born in Denmark. He discovered the proton. He won the Nobel Prize in 1922.

Sir James Chadwick

Jan 22, 1932

Sir James Chadwick
22 Jan 1932 Sir James Chadwick was born in the United Kingdom. In 1935, he was also awarded the Nobel Prize for his discovery of the nuetron.