... g of hydrogen Slide of 25 General Chemistry: Prentice-Hall © Behavior of charges Slide of 25 General Chemistry: Prentice-Hall © Cathode ray tube Slide of 25 General Chemistry: Prentice-Hall © ... 25 General Chemistry: Prentice-Hall © Early Discoveries Lavoisier 1774 Law of conservation of mass Proust 1799 Law of constant composition Dalton 1803-1888 Atomic Theory Slide of 25 General Chemistry: ... that originate in the nucleus Slide 10 of 25 General Chemistry: Prentice-Hall © The nuclear atom Geiger and Rutherford 1909 Slide 11 of 25 General Chemistry: Prentice-Hall © The α-particle experiment...