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Change in temperature if pressure changes?
If you have a stretchy, but insulated, spherical balloon and decrease the pressure from 1 atm to .5 atm while keeping the temperature outside of the balloon at a constant 298 K, what will the temperature inside the balloon be?
1 Answer
- GeniusLv 41 decade agoFavourite answer
Assuming a (perfectly) insulated balloon, the outside temperature is irrelevant. The initial inside temperature of the air is what matters and I'll take it as 298K.
In general, pressure (P), volume (V), and temperature (T), of a gas are related:
PV/T = k
In order to determine the temperature change, you would need to know both the volume and pressure changes. Usually one is held constant while the other is changed, making the temperature change very simple to calculate.
So we need to know the pressure inside the balloon, not the pressure outside the balloon which is what I assume you are reducing from 1 to 0.5. The pressure inside the balloon is not known from your question, and the volume change is also not known, so it is impossible to calculate the temperature.