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John Dalton (1766 - 1844)
John Dalton was an amazing English Chemist with a Quaker background and beliefs. Using many experiments he found out a lot about atoms such as:
All matter is made of atoms. Atoms are indivisible and indestructible.
All atoms of a given element are identical in mass and properties.
To find out more about him go to:
http://www.iun.edu/~cpanhd/C101webnotes/composition/dalton.html -
J.J.Thompson (December 18, 1856 - August 30, 1940)
Joseph John Thompson was an English Scientist. He discovered the electron - the negative particle in an atom. He accidentally found it when experimenting with gas discharge tubes.There was a movement in the tubes, Thompson called this Cathode Rays. The rays would move from the negative end to the positive. The rays were made from negatively charged particles, electrons.
http://www.chemheritage.org/discover/online-resources/chemistry-in-history/themes/atomic-and-nuclear-structure/thomson.aspx -
Lord Ernest Rutherford (August 30, 1871 - October 19, 1937)
The maker of the famous Gold Foil experiment, and proved that atoms were mostly empty space. To conduct this famous experiment he used a very thin sheet of gold and special equipment to shoot alpha particles (positively charged particles) at the foil, and what he found out was very surprising, the particles would pass through as if nothing was there, others were deflected or went straight back as if they hit something.
He learned that atoms are made of a small positive nucleus.
