1. The problem statement, all variables and given/known data In a period of 1 s, 5 x 10^23 nitrogen molecules strike a wall with an area of 8 cm^2. Assume the molecules move with a speed of 300 m/s and strike the wall head-on in elastic collisions. What is the pressure exerted on the wall? (The mass of one N2 molecule is 4.68 x 10^-26 kg.) 2. Relevant equations P = 2/3(N/V)(1/2mo(v^2)avg = F/A = [mo/d(N)(v^2)]/A 3. The attempt at a solution I found the moles of N2 (I think this is how you do it, I was never strong in chemistry and haven't taken it in two years...) n = N/Na = 5 x 10^23/6.022x10^23 = 0.83 moles I believe n = N/V as well, so... P = 2/3(n)(1/2mo(v^2)avg I'm thinking I need to find the average speed... since I have vx, I can do the force one F = (4.68 x 10^-26)/d(5 x 10^23)(300^2) So I need to find 'd'... I'm stuck, I'm not sure whether to try and find 'd' (length of the wall the molecules are hitting), or try and find v.avg (I'm thinking I'd somehow do that with the time interval and the vx value, but I'm not sure how...) Thanks in advance.