Timeline: Chem - Atom Thing

Period: 450 to 2020

History of The Atomic Theory

Sources:
google.com
https://en.wikipedia.org/wiki/Democritus#Atomic_hypothesis
https://en.wikibooks.org/wiki/General_Chemistry/Atomic_Structure/History_of_Atomic_Structure

460

Democritus

Born: Abdera, Thrace
Contribution: Existence of indivisible atoms
Theory: All matter is composed of too small to be seen atoms, and can NOT be made smaller; There exists empty space between atoms; Atoms are completely solid; Atoms are homogeneous, with no internal structure; Atoms differ in size, shape, and weight.
Source: Work of Parmenides and Zeno
Interesting Facts: Disliked by Plato,

Sep 6, 1766

John Dalton

Born: Eaglesfield, England
Contribution: Atomic weights
Theory: (1803) Elements are composed of tiny particles called atoms; All atoms of a given element are identical; The atoms of elements are different from each other and different elements have different weights; Atoms can combine to form chemical compounds; Atoms cannot be created or destroyed
Source: Researches on ethylene and methane or by analysis of nitrous oxide
Interesting Facts: Colorblindness, Gas laws, Meteorology

Dec 18, 1856

JJ Thompson

Born: Manchester, England
Contribution: (1889) Electron
Theory: "Plum Pudding" Electrons were floating around in a mass of positive charge to make an electrically neutral atom
Source: Cathode Rays
Interesting Facts: He earned a total of eight awards

Aug 30, 1871

Ernest Rutherford

Born: Hornchurch, England
Contribution: Alpha Particles, Plum Pudding Wrong
Theory: Atoms have a nucleus containing the positive charge and most of the atom's mass; The atom consists of mostly empty space; Electrons are attracted to the nucleus, but remain far outside it
Source: Gold Foil Experiment
Interesting Facts: He and I were both born on Aug 30, Has an element named after him, Earned eleven awards

Oct 7, 1885

Niels Bohr

Born: Copenhagen, Denmark
Contribution: Structure of Atoms
Theory: Atom is a nucleus with electrons orbiting around it at specific distances
Source: Rydberg, Rutherford
Interesting Facts: He had six sons, two of which died early

Aug 12, 1887

Erwin Schrodinger

Born: Vienna, Austria
Contribution: Wave Mechanics
Theory: Viewed electrons as continuous clouds
Source: Einstien
Interesting Facts: Hitler was born in Vienna as well, Schrodingers Cat

Oct 20, 1891

James Chadwick

Born: Bollington, United Kingdom
Contribution: Neutron
Theory: Using alpha particles discovered a neutral atomic particle with a mass close to a proton
Source: Alpha Particles, Rutherford
Interesting Facts: Alive during WW1, POW 1913-1918

2017