Atire at 21°c has a pressure of 0.82 atm. its temperature decreases to –3.5°c. if there is no volume change in the tire, what is the pressure after the temperature change?

Answer : The pressure after the temperature change is, 0.75 atm.

Solution :

According to the Gay-Lussac's Law, the pressure is directly proportional to the temperature of the gas at constant volume and number of moles.

    (At constant volume and number of moles)

Or,

where,

= initial pressure = 0.82 atm

= final pressure = ?

= initial temperature =

= final temperature =

Now put all the given values in the above formula, we get the final pressure of the gas.

Therefore, the pressure after the temperature change is, 0.75 atm