1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Gases and Average Speed

  1. Apr 27, 2012 #1
    1. The problem statement, all variables and given/known data

    The gases in this room include oxygen (molar
    mass 32 g), nitrogen (28 g), water (18 g), and
    carbon dioxide (44 g). Which type of molecule has
    the highest average speed?

    A) O2
    B) N2
    C) H2O
    D) CO2
    E) They have the same average speed.

    2. Relevant equations

    1/2 mv^2 = 3/2 kT

    3. The attempt at a solution

    Is the answer water because it's mass is the smallest?
     
  2. jcsd
  3. Apr 27, 2012 #2
    The molecular speed of gases at constant temperature varies inversely with the square root of the molecular mass. So the lightest molecule will go the fastest.
     
  4. Apr 27, 2012 #3
    Thanks for replying. Sorry if it seemed obvious - I'm doing review problems without looking at the answers.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Gases and Average Speed
  1. Average speed (Replies: 3)

  2. Average speed (Replies: 1)

  3. Average speed (Replies: 1)

  4. Average speed (Replies: 2)

Loading...