Question

1. An ideal gas at 40psig and 80 degree F is heated in a closed container to 120 degree F. What is the final pressure, psia?

Answer 1

Convert 80 F and 120 F to C.
Convert 40 psig to psia. 40+14.7 = ? psia.
Then (P1/T1) = (P2/T2) and solve for P2. P2 will be in psia.

Answer 2

Don't forget to convert C (after you've converted F to C) to Kelvin.
K = 273.15 + C
If this is an engineering problem you can use Rankin