Originally Posted by ipchay61
Nitrogen is not lighter than 'air' and the molecules are not larger....check your periodic charts. The only benefit of using Nitrogen is that it doesn't absorb water and therefor will have a more predictable increase in tire pressure as it heats up. Possibly there could be slightly less oxidation on the inside of the tire but since the atmosphere already is ~78% Nitrogen, I really doubt that would show any benefit.
-Chip in SC
N2 and O2 molecules are actually almost the same size and N2 is lighter than O2 (28 g/mol vs 32 g/mol). And if you go strictly by atomic weight, pure nitrogen is considerably lighter than dry air (78.1% Nitrogen, 20.9% Oxygen, 0.93 % Argon & trace (<.1%) amounts of other noble gases, carbon dioxide and air pollutants). Have to go now... Late for 3rd period science class