Why nitrogen in tires?

Question

The rate of diffusion has nothing to do with the size of the molecule but rather its molecular weight. The rate of diffusion is inversley proportional to the square root of the molecular weight. As far as making tires run cooler, the specific heats and thermal conductivities are almost identical so no advantage. All gases follow the same laws of physics so far as volume and pressure are affected by temperature so no advantage. I have seen no hard evidence that it reduces oxidation under typical driving conditions. I think someone is getting rich selling something that is contained in air at an 80% level.

Answer 1

you will find that a tire filled with air will go down nautrally but one with nitrogen in will not it is used in formula 1 cars so you could try looking on the web sites to see if you can email the enginers hope this helps

Answer 2

Many times I have seen claims that nitrogen does not behave as air does as far as expansion and heat dissipation are concerned; which is just pure bullock (air is still 78% nitrogen, so air should always overwhelmingly behave like pure nitrogen)
That said, one thing that pure nitrogen has (or actually lacks) as compared with air is moisture content. Air naturally contains moisture which may condense in tires or turn into vapor depending on the current temperature. For aircraft tire, given that airliners cruise at 31000 ft and above, where the temperature can be as low as -70 F (-56 C) having that water turn into ice may severely unbalance a tire when the time comes to use it for landing.
A final thing that could sway the balance in favor of nitrogen: the oxygen in the air is still a fairly active substance and can react and slowly degrade the rubber from the inside. But given that the *outside* of tires is already subjected to such an attack, and that we do not see much except mild discoloration due to oxidation, that advantage is very slim indeed.
So, using very dry air should do the same as nitrogen.
And even those who insist on nitrogen, does anyone have the capability to check if what is being sold is not *plain air* in the first place?

Answer 3

It's a rip off at ten bucks a tire. They always argue that nitrogen will seep out of a tire more slowly than oxygen but never remind you of the concentration of nitrogen in the air.

Answer 4

I doubt anyone is getting rich on the idea because nobody will use it for conventional road vehicles - unless they have more money than sence.

Answer 5

Nitrogen is very unreactive and thus can be transported easily and is also lighter than air.

Answer 6

Doesn't it improve the properties of the rubber in the tire? I don't know, just asking.

Answer 7

and nitrogen smells bad too.

Answer 8

I think your absolutely right