Register to reply 
Boltzmann equation problem 
Share this thread: 
#1
Sep1707, 10:03 AM

P: 569

1. The problem statement, all variables and given/known data
Consider a pure hydrogen hydrogen gas ata tempeature of 10080 K. What is the ratio of the populations of the ground state(n=1) to the first excited state(n=2). Note that the energy difference is 1.634e18 joules between these two states. At what temperature would both levels have equal populations? 2. Relevant equations Boltzmann equation: N(B)/N(A)= g(b)/g(a) exp[(E(A)E(B))/kT g=2*n^2 3. The attempt at a solution finding N(B)/N(A) was easy. N(2)/N(1)=2(2)^2/2(1)^2*exp(1.634e18 joules)/(10080 K)(1.380 *10^23))= .000031665 I had a difficult time finding the Temperature when both populations are equal. When both populations are equal, does that imply N(a)/N(b) = 1 because N(a)=N(B)? Now finding the temperature is simple : 1=4 exp(1.634e18 joules/(T(1.380e23)) => T= 85411.7 Kelvins. The only problem is I don't know if I should assume N(B)/N(A) = 1 , just because the temperatures are equal 


#2
Sep1707, 11:07 AM

Sci Advisor
HW Helper
P: 4,300

No, you shouldn't assume N(B)/N(A) = 1 because the temperatures are equal.
You should assume it because you assume that the populations are equal; then you fill in the formula and solve for the temperature where this occurs. So you have obtained the right answer with the right method but with a wrong way of thought 


#3
Sep1707, 01:24 PM

P: 569




#4
Sep1707, 01:47 PM

Sci Advisor
HW Helper
P: 4,300

Boltzmann equation problem
Then you got the right answer by the right method and a typo :)



Register to reply 
Related Discussions  
Boltzmann Equationwhere'd the 3 come from?  General Physics  4  
Boltzmann distribution  Introductory Physics Homework  18  
Boltzmann equation/ Statistical Mechanics  Advanced Physics Homework  4  
Linearizing StefanBoltzmann equation  Advanced Physics Homework  2  
Boltzmann distribution  General Physics  1 