History of the Atom

Democritus

442

• Greek philosopher.• Changed history of the atom by coming up with theory that matter is indivisible.• Born 460 BC• Died 370 BC• Matter is indivisible

John Dalton

Sep 6, 1766

• A British chemist and physicist.• Changed history of the atom by coming up with theory that matter is simply composed of atoms of different weights and is combined in ratios by weight.• Born 6th Sept 1766• Died 27th July 1844• Matter is composed of atoms of different weights

Michael Faraday

Sep 22, 1791

• Born 22nd Sept 1791• Died 25th Aug 1867• Developed laws of electrolysis.• Was and English scientist

George Stoney

Feb 15, 1826

• Born 15th February 1826• Died 5th July 1911• Introduced the term electron into physics• Anglo-Irish physicist• Published over 70 scientific papers during his life

James Maxwell

Jun 13, 1831

• Born 13th June 1831• Died 5th November 1879• Formulated set of equations• Scottish theoretical physicist • Demonstrated that electricity, magnetism and light are all the same phenomenon.

William Crookes

Jun 17, 1832

• Born 17th June 1832• Died 1919• Discovered properties of cathode rays

Dmitri Mendeleev

Feb 8, 1834

Created the first version of the periodic table
Born February 8th 1834

Died February 2nd 1907

Russian Chemist and Inventor

Wilhem Rontgen

Mar 27, 1845

• Born 27th March 1845• Died 10th February 1923• Produced and detected electromagnetic radiation• Earned first Nobel Prize in physics in 1901

Eugene Goldstein

Sep 5, 1850

• Born September 5th 1850• Died December 25th 1930• German Physicist• Credited with the discovery of the proton• Discoverer of anode rays• Early investigator of anode rays

Max Planck

Apr 23, 1858

•Born April 23 1858•Died October 4 1947•German theoretical physicist•Originated quantum theory•Won Nobel prize in physics in 1918

Ernest Rutherford

Aug 30, 1871

•Born 30th August 1871•Died 19th October 1937•New Zealand born British chemist and physicist•Established properties of the nucleus•Also assumed that the location of electrons was outside the nucleus.

Frederick Soddy

Sep 2, 1877

•Born 2nd September 1877•Died 22nd September 1956•English radio chemist •Discovered that radioactivity is due to the transmutation of elements•Proved the existence of isotopes

Niels Bohr

Oct 7, 1885

•Born 7th October 1885•Died 18th November 1962•Danish physicist•Made foundational contributions to atomic structure•Received Nobel Prize in physics in 1922

Henry Gwyn Jeffreys Moseley

Nov 23, 1887

•Born 23rd November 1887•Died 10th August 1915•English physicist •Discovered that the atomic number of an element is equal to the number of protons in the nucleus

Louis de Broglie

Aug 15, 1892

•Born 15th August 1892•Died 19th March 1987•French physicist •Discovered that electrons had a dual nature •Supported Einstein