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!

Ideal gas theory

  1. Jul 13, 2010 #1
    1. The problem statement, all variables and given/known data

    a) An ideal gas has a pressure of 1atm, volume of 0.5m^3m temperature of 300k. Find the number of moles.

    b) Three moles of an ideal gas is at a pressure of 1x10^2 Nm^-2 and a temperature of 263K. Calculate the volume.

    2. Relevant equations

    1) PV = NRT
    2) PV=NKbT

    R = gas constant; Kb = Boltzman's constant

    3. The attempt at a solution

    I have found the answers to be a) 1.22x10^23moles and b) 65.6m^3.

    What I don't understand, is when to use which equation. Why can I not use equation 1) for question a) vice versa.

    Thanks.
     
  2. jcsd
  3. Jul 13, 2010 #2
    Answer (a) is wrong. In PV = nRT, the "n" stands for moles. In PV = NkT, the "N" stands for number of molecules. There are 6.022 x 1023 molecules in a mole.
     
  4. Jul 13, 2010 #3
    Sorry that was meant to be 1.22x10^25 molecules.

    Thank you for explaining.
     
  5. Jul 13, 2010 #4
    Okay. I didn't check your math, but aren't you asked for the number of moles, rather than the number of molecules?
     
  6. Jul 13, 2010 #5
    Woops I was meant to write molecules instead of moles for question a) in my first post.

    Must remember to re-read my posts before submitting them. Sorry about that!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Ideal gas theory
  1. Ideal Gas (Replies: 4)

  2. Ideal gas (Replies: 5)

Loading...