Combined Gas Law + Ideal Gas Law Problem Set
Perform the following calculations. Determine whether the ideal or combined gas law needs to be used
based on the data given.
Given: PV=nRT
P1V1 = P2V2
R = 8.314 L∙kPa
R = 0.0821 L∙atm
1 L = 1000 mL
T1
T2
mol∙K
mol∙K
1. Calculate the volume of gas at STP if 5.05 L of the gas are collected at 27.5oC and 95.0 kPa.
2. When a balloon is placed in an oven at 1.2 atm and a temperature of 87 oC, the volume expands to 31.0
L. How many moles are present in the balloon?
3. If I have 0.275 moles of gas at 75 K and a pressure of 177 kPa, what is the volume of the gas?
4. A gas occupied 355 mL at a pressure of 99.5 kPa and a temperature of 22 0C. The pressure increases 10
kPa and the temperature drops 7oC. What is the new volume?
5. If I have 4 moles of gas at a pressure of 5.6 atm and a volume of 12 L, what is the temperature in
Celsius?
6. If I have 76.8 g of O2 at a temperature of 97oC in a container with a volume of 45 L, what is the pressure
of the gas in kPa?
7. Assume the respiratory rate for a person is 15 breaths per minute and one breath contains 500 mL of
air at 20oC and 99.5 kPa. What volume of air, corrected to STP, does an individual breathe in one day.
8. If I have an unknown quantity of helium at a pressure of 0.5 atm, a volume of 25 L, and a temperature
of 300 K, how many grams of helium do I have?