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KE of Gas Molecules

  1. Apr 19, 2010 #1
    I know that KE=3/2KbT, but doesn't the KE of gas molecules also equal U=3/2nRT? When do I use which? And also for the second equation if it is for a monoatomic gas, n=1, why isn't the n deleted?
  2. jcsd
  3. Apr 19, 2010 #2

    Vanadium 50

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    Look at the relationship between k, R and Avagadro's number.
  4. Apr 19, 2010 #3
    K=R/(Avagadro's Num), so 3/2*R/(Avagadro's Num)*T=3/2nRT
    getting rid of the same constants I get 1/(Avagadro's Num)=n
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