Answer:
The volume of a gas will decrease.
Let's think of some good examples. How about an air tank? Its volume is very small but the gas it contains could easily fill a small room. How is the volume so small, then? Because the gas is under extremely high pressure.
Okay so intuition from every day life tells us increase in pressure means decrease in volume.
Examples of temperature? A hot air balloon is filled by a flame that heats the gas inside it. The balloon gets bigger - the volume rises. This is an especially relevant example since the hot air balloon rises due to buoyancy, meaning the air inside it is less dense than the air outside it.
Less dense means there is less mass per volume inside it, so again we know that the gas inside the balloon has undergone an increase in volume in response to being heated.
So increase of temperature means an increase of volume.
The answer to your question, then, is that the volume will decrease (which is actually kinda difficult to do sometimes...but still a theoretical fact).
For further reading and understanding, see "Ideal gas law".
Explanation:
