1. The problem statement, all variables and given/known data According to statistical mechanics, the average kinetic energy of a particle at temperature T is 3kT/2, where k is the Boltzmann constant. What is the average de Broglie wavelength of nitrogen molecules at room temperature? 2. Relevant equations KE = 3kt/2 = p2/2m λ = h / p 3. The attempt at a solution So p = (2KEm)1/2, and inserting KE = 3kt/2 p = (3kTm)1/2 And thus λ = h/p = h / (3kTm)1/2 The only problem I have is that it seems like the units don't work out. Inserting the units only into h / (3kTm)1/2 : (kg m2 /s2)/((m2 kg/s2 K)(K)(kg))1/2 = (kg m2 /s2)/(m kg/s) = m/s, not m Am I simplifying the units wrong or is the equation wrong?