Sample Problems – Chapter 12
1. A 1.00 L sample of gas at 760 torr is compressed to 0.800 L at constant temperature.
Calculate the final pressure of the gas.
2. Calculate the volume which 4.00 L of gas at 0°C will occupy at 100°C and the same
pressure.
3. A sample of gas occupies 2.00 L at 760 torr. Calculate the volume it will occupy at 1.25 atm
and the same temperature.
4. Calculate the temperature at which a 2.00 L sample of gas at 27°C would occupy 3.00 L if its
pressure were changed from 1.00 atm to 800 torr.
5. A 4.00 L sample of gas at 30°C and 1.00 atm is changed to 0°C and 800 torr. What is its new
volume?
6. A sample of gas at 1.20 atm and 27°C is heated at constant pressure to 57°C. Its final volume
is 4.75 L. What was its original volume?
7. A mass of oxygen occupies 7.00 L under a pressure of 740 torr. Determine the volume of the
same mass of gas at standard pressure, the temperature remaining constant.
8. Determine the volume occupied by 4.0 g oxygen at STP.
9. What volume of hydrogen will combine with 22 L of chlorine to form hydrogen chloride?
What volume of hydrogen chloride will be formed? Assume the same temperature and
pressure for all gases.
10. What volume of hydrogen will unite with 16 ft3 of nitrogen to form ammonia? What volume
of ammonia will be produced, all at the same temperature and pressure?
11. Calculate the volume of 0.3000 mol of a gas at 60°C and 0.821 atm.
12. Calculate the volume of 8.40 g N2 and 100°C and 800 torr.
13. What mass of argon occupies 19.3 L at 90°C and 735 torr?
14. Determine the density of H2S gas at 27°C and 2.00 atm.
15. A 1.00 L vessel containing 1.00 g H2 gas at 27°C is connected to a 2.00 L vessel containing
88.0 g CO2 gas, also at 27.0°C. When the gases are completely mixed, what are the partial
pressures and total pressure (in atm)?
16. Into a 5.00 L container at 18°C are placed 0.200 mol H2, 20.0 g CO2, and 14.00 g O2.
Calculate the total pressure in the container and the partial pressure of each gas.
17. Determine the approximate molecular weight of a gas if 560 mL weighs 1.80 g at STP.
18. At 18°C and 765 torr, 2.29 L of a gas weighs 3.71 g. Calculate the approximate molecular
weight of the gas.
19. Calculate the MW of a gas which has a density of 1.48 g/L at 100°C and 600 torr.
20. Calculate the volume of O2 which can be prepared at 60°C and 760 torr by the decomposition
of 20.0 g H2O2 to H2O and O2.
21. What volume of hydrogen at 27°C and 680 torr is produced by the reaction of 15.0 g
aluminum metal with excess hydrochloric acid? The other product is AlCl3.
22. What volume of O2 at STP is required for the complete combustion of 1.00 mol of carbon
disulfide, CS2? What volumes of CO2 and SO2 at STP are produced?