Question

A 3.5-L sample of helium gas, collected at 0.00°C and 1.00 atm, is compressed into a 0.50-L cylinder. What pressure will the gas exert in the cylinder at 39.1°C?

Answer 1

The pressure of a gas is directly proportional to its temperature and inversely proportional to its volume.

PV/T = PV/T

(1.00atm * 3.5 L)/ 273k = (P * 0.50L)/(39.1 + 273k)
Do some simple algebra and you will get
P = 8.0 (Note that there should be 2 sigfigs)