1. Otto von Guericke (1602 – 1686) (Vacuum Pump – 1654) The Historical Gas Laws Boyle’s Law

2. Robert Boyle (1627 – 1691)

6. Jacques Charles (1746 – 1823)Joseph Louis Gay-Lussac (1778 – 1850) Charles’ or Gay-Lusacc’sLaw

7. Temp [oC]Volume [cm3] (P=1 atm) Volume [cm3] (P = 2 atm) 26.852443012120 36.852526412544 46.852609412967 56.852692913389 66.852775913810 76.852858814229

9. Ideal Gas Temperature Scale William Thomson, Lord Kelvin (1824 – 1907) Single Fixed Point Triple Point of Water 273.16 K

10. Law of Combining Volumes Joseph Louis Gay-Lussac (1778 - 1850) The ratio between the volumes of the reactant gases and the products can be expressed in simple whole numbers.

13. Equal Volumes of Gas Contain Equal Numbers of “Particles”

14. Problems Interpreti ng Combining Volume Data Assume Water’s Chemical Formula is HO

15. Assume Water’s Chemical Formula is H 2 O

16. The Answer! Amedeo Avogadro (1776 - 1856) Stanislao Cannizzario (1826 - 1910)

17. H2H2 O2O2 H2OH2O

18. Meyer’s Reaction to Cannizzaro It was as though the scales had been lifted from my eyes. Doubt vanished and was replaced by a feeling of peaceful clarity. Julius Lothar von Meyer (1830 – 1895)

19. Density Data Dimethyl Ether