If a balloon containing 1.200 L of gas at 25°C and 760 mmHg pressure ascends to an altitude where the pressure is 380 and the temperature is 54°C, what will the volume be?

1 Answer
Jan 12, 2017

We use the old relationship: P1V1T1=P2V2T2

Explanation:

Of course, we must use values of absolute temperature. Given the proportionality we could units of pressure and volume of foot pounds or atmospheres or gallons so long as we are consistent. Of course, I will use units of litres, and atmospheres.

V2=P1V1T1×T2P2=

1.200L×1atm293K×327K380mmHg760mmHgatm12.7L

But don't trust my arithmetic. You have to do this on paper, and make sure all the given units cancel out to give an answer in litres as required for a volume. Note that since we decrease the pressure, and INCREASE the temperature, the rise in volume is consistent with our expectation.