Answer
No, this would halve the gas pressure
Work Step by Step
The gas law is
PV = nRT
If we double the volume and keep the temperature constant then we have V = 2V so:
P(2V) = nRT
In order to balance both sides, we need to double the right side or halve the left side but we are told T is constant so we would have:
(1/2 P)(2V) = nRT
Therefore, this would halve the gas pressure