The temperature of a sample of an ideal gas confined in a 2.0 L container was raised from 27 °C to 77 °C. If the initial pressure of the gas was 1200 mm Hg, what was the final pressure of the gas?
Solution
Step 1
Convert temperatures from Celsius to Kelvin
K = °C + 273
Initial temperature (Ti): 27 °C
K = 27 + 273
K = 300 Kelvin
Ti = 300 K
Final temperature (Tf): 77 °C
K = 77 + 273
K = 350 Kelvin
Tf = 350 K
Step 2
Using the ideal gas relationship for constant volume, solve for the final pressure (Pf)
Pi / Ti = Pf / Tf
solve for Pf:
Pf = (Pi x Tf) / Ti
Pf = (1200 mm Hg x 350 K) / 300 K
Pf = 420000 / 300
Pf = 1400 mm Hg
Answer
The final pressure of the gas is 1400 mm Hg.

