Answer: decreases
The temperature of a gas decreases when the pressure decreases at constant volume
Step-by-step explanation:
The statement of Pressure Law states that the pressure of a given mass of gas is directly proportional to its absolute temperature provided the volume is kept constant.
Mathematically, it is expressed as
P α T
P = kT
or P/T = k
Thus, the direct proportionality of temperature and pressure makes temperature of a gas decreases when the pressure decreases and increases when pressure increases.