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!

Thermodynamics and Gas expansion

  1. Jan 16, 2006 #1
    Here's the Question:
    In a Classroom there are 50 rows of students. A container of N20 (laughing gas) was opened at the front row and tear gas (molar mass 240 gm/mole) was opened simultaneously at the rear of the room. Which row of students will be the first to be laughing with tears in their eyes? mm(N)=14 & mm(O)=16
    I thought I could solve it by using KE=3/2 KT and then after finding out the kinetic energy... substitute and solve for Velocity in KE=1/2 mv²
    However.. in the problem it doesn't say anything about the temperature in the room so I dont know if i should assume that it's room temperature or if there's another way to solve this... Any help is appreciated.
  2. jcsd
  3. Jan 17, 2006 #2


    User Avatar
    Science Advisor
    Homework Helper

    I think it's safe to assume the temperature is uniform throughout the room. You only need the relative thermal speeds of the molecules to determine where the two "diffusion fronts" will meet.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Thermodynamics and Gas expansion
  1. Expansion of a gas (Replies: 12)