300 ml of a gas at 27oC is cooled to 3oC at constant pressure.its final volume is? [please explain clearly]

Answer 1

You know that PV=kT
Since P is held constant, that means that

V/T = k/P, which is constant.

The temperature is reduced by a factor of (273+3)/(273+27), so the volume must also decrease by the same factor for V/T to remain constant.