Answer
Yes, this would double the pressure.
Work Step by Step
We have PV = nRT
If we halve the volume we have
P(1/2 V) = nRT
To balance it, we need to halve the right side or double the left side but we are told the Temperature is constant so we must double the pressure. This gives:
2P (1/2V) = nRT
or
PV = nRT
Therefore, this would double the pressure.
