You place a balloon in a closed chamber at standard temperature and pressure (STP). You cool the chamber to half of its original temperature while leaving the pressure constant. What happens to the balloon?

It stays the same volume.

It decreases to one-half of its original volume.

It doubles in volume.

It expands to four times its original volume.

Question

You place a balloon in a closed chamber at standard temperature and pressure (STP). You cool the chamber to half of its original temperature while leaving the pressure constant. What happens to the balloon?

       It stays the same volume.

       It decreases to one-half of its original volume.

       It doubles in volume.

       It expands to four times its original volume.

anonymous · Answer

PV = NrT

Pressure is the same so we can take that out
V = NrT
The number of molecules is constant and so is the universal gas constant so we can change those into k

Therefore V = kT
Since V is now proportional to the temperature we can therefore say that as the temperature decreases, the volume of the balloon will decrease.

This is of course assuming that the gas in the balloon also decreases in temperature.

anonymous · Answer

It decreases to one-half of its original volume., for sure?

anonymous · Answer

Pretty sure, yeah.

anonymous · Answer

You also have to assume that there is gas being fed into the room because otherwise the pressure would decrease in the room, counteracting the temperature difference, therefore causing the balloon to stay the same size.
The question covers this though by saying that there is a constant pressure