1. The problem statement, all variables and given/known data Helium gas with T1 = 500K and P1 = 0.02MPa in a rigid container with volume V = 1 cm^3. Then Helium goes through a process where atoms with kinetic energies greater than kB*T1, where kB is Boltzmann constant, are instantaneously removed from the container. Atoms remaining in the container attain a M-B velocity distribution with a final Temperature T2. Calculate T2 and the final pressure P2. 2. Relevant equations (1) PV = N * kB * T M-B speed distribution: (2) f(v) = 4 * pi * v^2 * (m / (2*pi*kB * T))^(3/2) * exp( - m * v^2 / (2 * kB * T)) 3. The attempt at a solution First, I find the number of molecules using (1) and the total number of atoms in state 1 is 2.987e18. Then find the limiting velocity by setting E = kB* T = 1/2 * m * v^2 to solve for v, integrate from 0 to v ( f(v) dv ) to find the fraction of the atoms up to this speed v = 0.463. The remaining atoms will be this fraction multiply by the number of atoms = 1.34e18 atoms remaining. Then I am lost on solving for T2 with this remaining atoms that attain M-B velocity distribution. Any help will be appreciated. Thanks!