John Dalton

John Dalton discovered atoms that were different elements combined in whole-number ratios to form compounds. In a chemical reaction, atoms are combined, rearranged, or separated. Dalton discovered all atoms of the same element are identical, and all matter is composed of extremely small particles called atoms. They are all indivisible.

J.J. Thomson

J.J. Thomson was credited for the "Plum pudding model". Thomson used the Cathode Ray Tube to figure out that particles were deflected and therefore particles were charged. Thompson figured out that atoms are a ball of positive charge with electrons on the outside surface. J.J.provided the beginnings of the development of a scientific atomic theory.

Ernest Rutherford

Ernest Rutherford discovered that atoms are mostly empty space with particles packed very tight into a dense center. They have a positive charge to the particles. Rutherford used the gold foil experiment. His explanation of radioactivity earned him the 1908 Nobel Prize in chemistry.

Niels Bohr

Niels Bohr Proposed the planetary model. He figured out that electrons travel in fixed pathways around the nucleus called energy levels. Niels created the first successful explanation of the hydrogen spectrum. The Bohr theory of the atom has become the foundation of modern atomic physics and is still used today.

James Chadwick

James Chadwick received the Nobel Prize in 1935 for his great discovery of the neutron. Chadwick himself was actively involved with the development of the atomic bomb. Chadwick developed a method to measure radioactivity that required the observation of flashes, called scintillations, in zinc sulfide crystals under a microscope and in complete darkness.

Erwin Schrödinger

Erwin Schrödinger shared the 1933 Nobel Prize for physics. In recognition of his development of a wave equation describing the behavior of an electron in an atom. He Proposed a probability equation for the location of the electron. It was also Known as the wave model. Electrons do not move in a definite pathway, Electrons stay in the electron cloud.

Citations:

John Dalton: "John Dalton." Encyclopedia of World Biography, Gale, 1998. Student Resources In Context, http://link.galegroup.com/apps/doc/K1631001669/SUIC?u=j043905010&sid=SUIC&xid=419397e2. Accessed 30 Aug. 2018. https://commons.wikimedia.org/wiki/File:John_Dalton_by_Charles_Turner.jpg

J.J. Thomson: "J. J. Thomson." DISCovering Biography, Gale, 2003. Student Resources In Context, http://link.galegroup.com/apps/doc/EJ2102101823/SUIC?u=j043905010&sid=SUIC&xid=853950a1. Accessed 30 Aug. 2018. https://www.google.com/search?q=jj+thomson&safe=strict&tbm=isch&source=lnt&tbs=sur:fc&sa=X&ved=0ahUKEwihg-WfgJTdAhWj3oMKHX3fChEQpwUIHg&biw=1440&bih=826&dpr=1#imgrc=S-kI8Oc5KhKPMM:

Ernest Rutherford: "Ernest Rutherford." DISCovering Biography, Gale, 2003. Student Resources In Context, http://link.galegroup.com/apps/doc/EJ2102101616/SUIC?u=j043905010&sid=SUIC&xid=4c6b4172. Accessed 30 Aug. 2018 https://www.google.com/search?q=ernest+rutherford&safe=strict&tbm=isch&source=lnt&tbs=sur:fc&sa=X&ved=0ahUKEwjN-fPlgJTdAhWp5oMKHa8MANgQpwUIHg&biw=1440&bih=826&dpr=1#imgrc=L1pGSps6eseJ7M:

Citations:

Niels Bohr: "Niels Henrik David Bohr." Encyclopedia of World Biography, Gale, 1998. Student Resources In Context, http://link.galegroup.com/apps/doc/K1631000761/SUIC?u=j043905010&sid=SUIC&xid=94b2159f. Accessed 30 Aug. 2018. https://www.google.com/search?q=niels+bohr&safe=strict&tbm=isch&source=lnt&tbs=sur:fc&sa=X&ved=0ahUKEwi02Zy0gZTdAhVl0YMKHUO3DKIQpwUIHg&biw=1440&bih=826&dpr=1#imgrc=1EUB35OzrPfr3M:

James Chadwick: "James Chadwick." DISCovering Biography, Gale, 2003. Student Resources In Context, http://link.galegroup.com/apps/doc/EJ2102100324/SUIC?u=j043905010&sid=SUIC&xid=9c1fb9e0. Accessed 30 Aug. 2018 https://www.google.com/search?safe=strict&biw=1440&bih=826&tbs=sur%3Afc&tbm=isch&sa=1&ei=MnyHW__yKOvgjwSFiLi4CA&q=james+chadwick&oq=james+&gs_l=img.1.0.0i67k1l3j0l2j0i67k1j0l4.50004.50907.0.52318.6.5.0.1.1.0.163.370.1j2.3.0....0...1c.1.64.img..2.4.370....0.qDaUMrAYbVw#imgrc=ESjfqdRLjPGXOM:

Erwin Schrödinger: "Erwin Schrödinger." DISCovering Biography, Gale, 2003. Student Resources In Context, http://link.galegroup.com/apps/doc/EJ2102101650/SUIC?u=j043905010&sid=SUIC&xid=50e5338e. Accessed 30 Aug. https://www.google.com/search?safe=strict&biw=1440&bih=826&tbs=sur%3Afc&tbm=isch&sa=1&ei=Z3yHW-WKJJWRjwTHlZSYDQ&q=erwin+schr%C3%B6dinger&oq=erwin&gs_l=img.1.0.0i67k1j0l3j0i67k1l2j0l4.81164.107707.0.109533.24.13.9.2.2.0.180.809.7j3.10.0....0...1c.1.64.img..3.21.843.0..0i10i30k1j0i5i30k1j0i24k1j0i10i24k1.0.2xaeExBQZ00 2018.