when the temperature of 4 dm3 of an ideal gas is increased from 200K to 400K and the pressure is halved, caculate the volume of the gas?

Answer 1

PV = kT
That means that
PV/T = k, a constant
So, making our changes, if V changes to aV,
(P/2)(aV)/(2T) = PaV/4T = PV/T * a/4
since the result must be equal to PV/T, a=4
That is, the Volume grows by a factor of 4.