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RMS speed of nitrogen molecule

  1. Jun 6, 2009 #1
    1. The problem statement, all variables and given/known data

    Compute the rms speed of a nitrogen molecule of 35.0 celcius.

    2. Relevant equations

    V(rms) = sqrt((3RT)/M)

    3. The attempt at a solution

    I plugged in 8.31 for R and 308 K for T and 14.0 g/mol for M. I arrived at a solution of 23.4 m/s but this answer came back as incorrect in online homework. However, I used this value to complete parts b and c to this question and correctly completed them. What gives?
  2. jcsd
  3. Jun 6, 2009 #2
    Did you change g to Kg?
  4. Jun 6, 2009 #3


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    Staff Emeritus
    Science Advisor
    Homework Helper

    A couple of questions to ponder:

    (a) If 1 mole of nitrogen atoms has a mass of 14.0 g, then a mole of nitrogen molecules has a mass of ____?

    (b) If 1 mole of nitrogen molecules has a mass of (insert answer to a here), then a single nitrogen molecule has a mass of ____?

    Also, as Dadface said, convert from g to kg.
  5. Jun 6, 2009 #4
    Nitrogen is a diatomic molecule. Thanks for the reminder...all is well.
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