It's whatever the data says it is. It'll be simplest to multiply both sides of your expression by T 2 . Solve that for n given the two midpoint estimates. NO 2 k 2 Derive the rate equation for the loss of N 2 O 5 by assuming that the intermediate NO 3 is in steady state. The nascent products of highly exothermic reactions are always highly vibrationally excited.
Atoms are spherical.
Molecules are not. The cross-section for N 2 differs with the process considered for it.