An automobile tire was inflated to a pressure of 24 lb in-2 (1.00 atm = 14.7 lb in-2 ) on a winter’s day when the temperature was –5 o C. What pressure will be found assuming no leaks have occurred and that the volume is constant, on a subsequent summer’s day when the temperature is 35 o C? What complications should be taken into account in practice?

Explanation:

Initial Pressure = 24 lb in-2

Initial Temperature = –5 o C = 268 K (Converting to kelvin temperature)

Final Pressure = ?

Final Temperature =  35 o C = 308 K (Converting to kelvin temperature)

No Change in Volume.

From Gay Lusaac's law; pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature.

P1T1 = P2T2

P2 = P1T1 / T2

P2 = 24 * 268 / 308 = 20.88 lb in-2

There would be a drop in pressure as the temperature increases. Appropriate measures should b taken by regularly gauging the pressure of the tire.