Chapter 5 - Additional Information

History of Chemistry (Taken liberally from: Wikipedia)

Early Atomic Theory


1783 - Antoine Lavoisier determines that oxygen combines with materials upon combustion, thus disproving phlogiston theory.
1789 - Antoine Lavoisier determines that chemical reactions in a closed container do not alter total mass. From these observations he establishes the law of conservation of mass Law of Conservation of Mass.


1807-1810 - Humphry Davy uses electrolysis to isolate elemental potassium, sodium, calcium, strontium, barium, magnesium, and chlorine.
1809 - Joseph Louis Gay-Lussac studies reactions among gases and determines that their volumes combine chemically in simple integer ratios.
1803-1810 - John Dalton proposes his atomic model.
1842-1843 - Julius Robert von Mayer and James Prescott Joule measure the heat generated by mechanical work. This establishes the principle of Conservation of Energy and the kinetic theory of heat.
18?? - Michael Faraday ?Need to find specific details about his work with Ions...though from reading the article he was the man on alot of things!
1884 - Svante Arrhenius studies the conductivity of salt solutions and determines that salts dissociate into ions in water.
1996 - Eugen Goldsteinfirst observes protons. They are later characterized by J. J. Thomson
1889 - Svante Arrhenius determines the impact of temperature on reaction rates and formulates the concept of Activation Energy.
1891 - George Johnstone Stoney develops the concept and properties of the magnitude of the "atom of electricity
1897 - J. J. Thomson discovers and characterizes the electron by his studies of Cathode Rays


1904 - J. J. Thomson proposes the Plum Pudding Model
1904-1914 - Fredrick Soddy proved the existence of Isotopes of radioactive elements.
1911 - Ernest Rutherford's Gold Foil Experiment demonstrated that the positive charge and mass of an atom is concentrated in a small, central atomic nucleus, disproving the then-popular plum pudding model of the atom (1911)
1912 - J. J. Thomson (again) studying Canal Rays discovers the existence of Isotopes of nonradioactive elements.
1932 - James Chadwick discovers the Neutron.