Question Given

I'm struggling with (i) and (ii). I understand how to do (iii) and (iv) as it is just an application of Graham's Law of Effusion twice and n times (solve for n) respectively. I am starting with

rate of effusion = -dN/dt = (1/2)(N/V)SQRT(2kT/pi*m)*dA

where N/V is the number density, k is boltzmann's constant, T is temperature, m is the mass of the molecule and dA is the area of the aperture.

When I do the ratio of rates for the 235:238 isotopes, I get:

(rate for 235)/(rate for 238) = (N_235/N_238)SQRT(m_238/m_235)

where N_235 and N_238 is the number of molecules of the 235UF6 and 238UF6 isotopes respectively and m is the mass of the molecules (or relative molecular mass).

I don't know how to get from where i am to the equation or have I gone completely wrong from the getgo?

  • 1
    $\begingroup$ Please do not post an image of the text you want to quote, but type it out instead so it is readable for all users and so that it can be indexed by search engines. For formulae, use MathJax instead. $\endgroup$ – Faded Giant Jan 3 at 10:22

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.