Subscription Info   Newsletter   Site Demo   Librarians   Help/FAQs   About   Contact Us    Search Options   Log In

< Back Argon  SEE PERIODIC TABLE   SEE FULL ARTICLE Atomic Number 18 Atomic Symbol Ar Atomic Weight 39.948 amu Group Noble Gas, 18 Form Gas Density @ STP 1.756 g/L Melting Point -189.35 °C (-308.83 °F, 83.8 °K) Boiling Point -185.85°C (-302.53 °F, 87.3 °K) Heat of Fusion 1.12 kJ/mol Heat of Vaporization 6.43 kJ/mol First Ionization Potential 15.75962 eV Specific Heat Capacity 0.520 J/g K Ground State Electron Configuration 3p6 Oxidation States 0 Stable Isotopes and Natural Abundance on Earth 36Ar, 0.337%; 38Ar, 0.063%; 40Ar, 99.600% Atomic Radius 71 pm Crystal Structure Cubic Discovered by Ramsay; Rayleigh, 1894

Copyright ©2008 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use and Privacy Notice. Additional credits and copyright information.