Answer:
Step-by-step explanation:
It is a physical change .
If we start from 10 atm of pressure and - 40 celsius of temperature to 20 atm of pressure and 70 celsius of temperature , it is a change in which pressure increases and temperature also increases that means heat is added up to the gas . If we cool the gas we can retrieve its earlier pressure and temperature .
So it is a physical change . In physical change , we can retrieve the old position by simple means.