Armand explained to his friend Bertrand that, in general, if you have a gas container and the amount of gas is doubled, the new pressure will be double the old pressure. The term "general" is employed because this is not exactly accurate, but it is close enough for the purposes of answering his next query.

Armand now posited this question to Bertrand, "If you have a tire filled with the standard 32 psi and you double the amount of air molecules in the tire, what pressure will your tire gauge now read? Assume that the tire does NOT expand, and that the first paragraph containing my initial information is exactly true."

Bertrand immediately answered, "64 psi."
But, Armand replied back to him, "Your answer is incorrect!"

What is the correct answer and why?

(In reply to inexact solution by Charlie)

What's really interesting is that it's not difficult to see the two minor effects in the real world.  As an avid bicyclist, if I experience a flat tire in an inconvenient location, an alternative to using a hand pump is to carry a valve and several bb gun style CO2 cylinders, which typically are at about 850psi at room temperature.  However, if one empties the CO2 too quickly the cylinder gets cold enough to give you  frostbite.  Also,  when the cooled gas in the tire warms up to the outdoor temperature,  the pressure in the tire can rise by as much as 10psi.  The relatively small volume of a bike tire is what makes this effect easily observable.  

Posted by Kenny M on 2022-09-05 12:55:59