Register to reply

Kinetic Theory of Gases

by LCc
Tags: gases, kinetic, theory
Share this thread:
LCc
#1
May20-07, 07:33 PM
P: 150
1. The problem statement, all variables and given/known data
1) A container is filled with a mixture of nitrogen and oxygen. What is the ratio of the rms speed of oxygen molecules to that of a notrigen molecules? (molar mass of oxygen = 32 g/mol; molar mass of nitrogen = 28 g/mol)

2) By what factor does the rms speed of neon molecules increase if their temperature increased by a factor of 4?

2. Relevant equations

rms= squared, mean, root.

1/2mv=3/2KT where K = 1.83 x 10^-23 (Boltzmann's constant)
average velocity vectors of molecules = 0

3. The attempt at a solution

I'm completely clueless as to how to answer this question.
Phys.Org News Partner Science news on Phys.org
Hoverbike drone project for air transport takes off
Earlier Stone Age artifacts found in Northern Cape of South Africa
Study reveals new characteristics of complex oxide surfaces
Dick
#2
May20-07, 07:56 PM
Sci Advisor
HW Helper
Thanks
P: 25,251
(1/2)*m_O*v_O^2=(1/2)*m_N*v_N^2=(3/2)*k*T. Manipulate this to get a ratio of v_O to v_N. I.e. solve for v_O/v_N. Relatively the same approach for 2).
LCc
#3
May20-07, 08:08 PM
P: 150
I don't see how you can get rid of the masses and the other variables if they're not constants. The instructions give the molar masses of the gases which are obviously not the same. So, we can't cancel them out when manipulating the equations. May I ask what do you get as an answer?

Dick
#4
May21-07, 07:54 AM
Sci Advisor
HW Helper
Thanks
P: 25,251
Kinetic Theory of Gases

If I divide one expression by the other I get (m_O/m_N)*(v_O/v_N)^2=1. Does that help you to see where to go?
LCc
#5
May21-07, 12:00 PM
P: 150
Oh I see thank you, I got it. 0.935 :).


Register to reply

Related Discussions
Kinetic theory of gases Introductory Physics Homework 2
Kinetic theory of gases Advanced Physics Homework 3
Kinetic Theory of gases Advanced Physics Homework 1
Kinetic theory of gases Advanced Physics Homework 1