Arkansas State University
Department of Chemistry
and Physics
Gas Laws 2

1. A sample of 0.50 moles of gas is placed in a container of volume of 2.5 L.  What is the pressure of the gas in torr if the gas is at 25oC? P = 4.89 atm = 3719 torr

2. A sample of gas is placed in a container at 25oC and 2 atm of pressure.  If the temperature is raised to 50oC, what is the new pressure? P = 2.17 atm

3. At 1 atm of pressure water boils at 100oC, if the sample was placed under 2 atm of pressure, what would be the temperature?  (This would be like a pressure cooker).
T = 746 K = 473oC = 883oF

4. At what temperature would water boil if the pressure is 600 torr? (Use information from problem 3:  this shows why food doesn't cook well at higher elevations)
T = 294 K = 21.5oC = 70.7oF

5. Calculate the volume of 40.6 g of F2 at STP. V = 23.9 L

6. A sample of 2.0 moles of hydrogen gas is placed in a container with a volume of 10.4 L.  What is the pressure of the gas in torr if the gas is at 25oC? P = 4.70 atm = 3576

7. The tire pressure is 32 psi.  What is the pressure in torr if 1 atm = 14.7 psi?
P = 1654 torr

8. A gas is placed in a balloon with a volume of 3.0 L at 28oC and 900 torr.  What would be the new volume for the gas if placed under STP? V = 3.2 L

9. How many moles of gas would occupy a volume of 14 L at a  pressure of 700 torr and a temperature of 30oC? n = 0.52 mol

10. Calculate the volume of 24.0 g of HCl at STP. V = 14.8 L

11. What is the volume of one mole of acetylene gas at STP? V =22.414 L

12. What is the volume of 0.75 mol of gas at 72oC and 2 atm? V = 10.6 L

13. After eating beans, a student collects a sample of gas at 0.97 atm and 26oC which occupies a volume of 3.5 L, calculate its volume at STP. V = 3.1 L

14. Ammonia (NH3) is placed in 1.5 L flask at 25oC.  If the pressure of the gas is 0.899 atm, what is the density? d = 0.626 g/L

15. A mixture of Ar and CO gases is collected over water at 28oC and an atmospheric pressure of 1.05 atm.  If the partial pressure of Ar is 600 torr, what is the partial pressure of CO?  (vapor pressure of water at 28oC is 28.3 mmHg) PCO = 0.223 atm

16. Determine the partial pressures of each of the gases in the following mixture: 17.04 g NH3, 40.36 g Ne and 19.00 g F2.  The gases are at 1.5 atm of pressure.
PNH3 = 0.428 atm; PNe = 0.857 atm; PF2 = 0.2124 atm

17. Potassium chlorate decomposes under heat as follows:

 2 KClO3 (s)  ------->   2 KCl (s)  + 3 O2 (g)

 The oxygen gas is collected over water at 25oC.  The volume of gas is 560 mL measured at 1 atm.  Calculate the number of grams of KClO3 used in the reaction.  (vapor pressure of water = 0.0313 atm) nO2 = 0.022 mol; 1.81 g KClO3