CHAPTER 5 REVIEW PACKET – GAS LAWS

1. The typical atmospheric pressure on top of Mt.Everest (29,028 ft) is 265 torr. Convert the pressure to:

(a) atmospheres

(b) mm Hg

(c) kilopascals

2. A fixed quantity of gas at 23.00C exhibits a pressure of 735 torr and occupies a volume of 5.22 L.

(a) Determine the volume the gas will occupy if the pressure is increased to 1.88 atm and the temperature is held constant.

(b) Determine the volume the gas will occupy if the temperature is increased to 1650C while the pressure is held constant.

3. Nitrogen and hydrogen gas react to form ammonia gas as follows:

N2 (g) + 3 H2 (g) → 2 NH3 (g)

At a certain temperature and pressure, 1.20 L of N2 reacts with 3.60 L of H2. If all the N2 and H2 are consumed, what volume of NH3, at the same temperature and pressure, will be produced?

4. The Hindenburg was a hydrogen-filled dirigible that exploded in 1937. If the Hindenburg held 2.00 x 105 m3 of hydrogen gas at 23.00C and 1.00 atm, what mass of hydrogen was present?

5. A scuba diver’s tank contains 0.290 kg of O2 compressed into a volume of 2.30 L.

(a) Calculate the gas pressure inside the tank at 9.000C.

(b) What volume would this oxygen occupy at 26.00C and 0.950 atm?

6. Which gas is most dense at 1.00 atm and 298 K?

(a) CO2

(b) N2O

(c) Cl2

Explain:

7. Calculate the density of NO2 gas at 0.970 atm and 35.00C.

8. Calculate the molar mass of a gas if 2.50g occupies 0.875 L at 685 torr and 35.00C.

9. Chemical analysis of a gaseous compound showed that it contained 23.5% C, 1.98% H, and 74.5% F. At 22.30C, a 0.100g sample of the compound exerts a pressure of 70.5 mm Hg in a 256 mL container. Determine the molar mass of the compound and its molecular formula.

10. Magnesium can be used as a “getter” in evacuated enclosures, to react with the last traces of oxygen. (The magnesium is usually heated by passing an electric current through a wire or ribbon of the metal.) If an enclosure of 0.382 L has a partial pressure of O2 of 3.50 x 10-6 torr at 27.00C, what mass of magnesium will react according to the following equation?

2 Mg (s) + O2 (g) → 2 MgO (s)

11. The metabolic oxidation of glucose, C6H12O6, in our bodies produces CO2, which is expelled from our lungs as a gas:

C6H12O6 (aq) + 6 O2 (g) → 6 CO2 (g) + 6 H2O (l)

Calculate the volume of CO2 produced at body temperature (37.00C) and .970 atm when 24.5g of glucose is consumed in this reaction.

12. Hydrogen gas is produced when zinc reacts with sulfuric acid:

Zn (s) + H2SO4 (aq) → ZnSO4 (aq) + H2 (g)

If 159 mL of wet H2 is collected over water at 24.00C and a barometric pressure of 738 torr, how many grams of Zn have been consumed? Look up the water vapor pressure in the tables in the text.

13. A mixture containing 0.538 mol He(g), 0.315 mol Ne(g), and 0.103 mol Ar(g) is confined in a 7.00 L vessel at 25.00C.

(a) Calculate the partial pressure of each of the gases in the mixture.

(b) Calculate the total pressure of the mixture.

14. A quantity of N2 gas originally held at 4.75 atm pressure in a 1.00 L container at 26.00C is transferred to a 10.0 L container at 20.00C. A quantity of O2 gas originally at 5.25 atm and 26.00C and a 5.00 L container is transferred to the same container. What is the total pressure in the new container?

15. Place the following gases in order of increasing average molecular speed at 25.00C : Ne, HBr, SO2, NF3, and CO.

16. Calculate the rms velocity of NF3 molecules at 25.00C.

17. A gas of unknown molecular mass was allowed to effuse through a small opening under constant-pressure conditions. It required 105s for 1.00L of the gas to effuse. Under identical experimental conditions, it required 31.0s for 1.00L of O2 to effuse. Calculate the molar mass of the unknown gas.

18. Calculate the pressure that CCl4 will exert at 40.00C if 1.00 mol occupies 28.0L, assuming that

(a) CCl4 obeys the ideal gas equation

(b) CCl4 obeys the van der Waals equation

OVER