Chapter 11 Homework

11.1 Volume-Mass Relationships of Gases

1. At STP, what is the volume of 7.08 mol of nitrogen gas? soln

2. A sample of hydrogen gas occupies 14.1 L at STP. How many moles of the gas are present? soln

3. At STP, a sample of neon gas occupies 550. cm^{3}. How many moles of neon gas does this represent? soln

4. What is the mass of 1.33 x 10^{4} mL of oxygen gas at STP? soln

5. What is the volume of 77.0 g of nitrogen dioxide gas, NO_{2}, at STP? soln

6. At STP, 3 L of chlorine is produced during a chemical reaction. What is the mass of this gas. soln

7. Define molar volume.

8. How many moles of oxygen gas are there is 135 L of oxygen at STP? soln

**11.2 The Ideal Gas Law - The Ideal Gas Constant - Finding
P, V, T, or n from the Ideal Gas Law**

1. What pressure, in atmospheres, is exerted by 0.325 mol of hydrogen gas in 4.08 L container at 35^{0} C? soln

2. A gas sample occupies 8.77 L at 20^{0} C. What is the pressure, in atmospheres, given that there are 1.45 mol of gas in the sample? soln

3. A sample that contains 4.38 mol of a gas at 250 K has a pressure of 0.857 atm. What is the volume? soln

4. How many liters are occupied by 0.909 mol of nitrogen at 125^{0}C and 0.901 atm pressure? soln

5. How many grams of carbon dioxide gas are three in a 45.1 L container at 34^{0} C and 1.04 atm? soln

6. What is the mass, in grams, of oxygen gas in a 12.5 L container at 45^{0} C and 7.22 atm? soln

7. A sample of carbon dioxide with a mass of 0.30 g was placed in a 250 mL container at 400. K. What is the pressure exerted by the gas? soln

**11.3 The Ideal Gas Law - The Ideal Gas Constant - Finding
Molar Mass or Density from the Ideal Gas Law
**1. What is the molar mass of a gas if 0.427 g of the gas occupies a volume of 125 mL at 20.0

2. What is the density of a sample of ammonia gas, NH

3. The density of a gas was found to be 2.0 g/L at 1.50 atm and 27

4. What is the density of argon gas, Ar, at a pressure of 551 torr and a temperature of 25

5. What is the volume in liters, of 0.100 g of C

6. Name two quantities besides pressure, mass, volume, and number of moles that can be calculated using the ideal gas law.

1. Assuming all volume measurements are made at the same temperature and pressure, what volume of hydrogen gas is needed to react completely with 4.55 L of oxygen gas to produce water vapor according to the following balanced equation:

2 H

soln

2. What volume of oxygen gas is needed to react completely with 0.626 L of carbon monoxide gas, CO, to form gaseous carbon dioxide according to the following balanced equation:

2 CO + O_{2} ---> 2 CO_{2 }Assume all volume measurements are made at the same temperature and pressure. soln_{
}**11.5 Stoichiometry of Gases - Volume-Mass & Mass-Volume
Calculations
**1. What mass of sulfur must be used to produce 12.61 L of gaseous sulfur dioxide at STP according to the following balanced equation:

S

soln

2. How many grams of water can be produced from the complete reaction of 3.44 L of oxygen gas, at STP, with hydrogen gas according to the following balanced equation:

_{
} 2 H_{2} + O_{2} ---> 2 H_{2}O

soln

3. What volume of chlorine gas at 38^{0} C and 1.63 atm is needed to react completely with 10.4 g of sodium to form NaCl according to the following balanced equation:

2 Na + Cl_{2} ---> 2 NaCl

soln

4. How many liters of gaseous carbon monoxide at 27^{0} C and 0.247
atm can be produced from the burning of 65.5 g of carbon according to the following
equation?

2 C + O_{2} ---> 2 CO

soln

**11.6 Effusion and Diffusion**

1. A sample of hydrogen effuses through a porous container about 9 times faster than an unknown gas. Estimate the molar mass of the unknown gas. soln

2. Compare the rate of effusion of carbon dioxide with that of hydrogen chloride at the same temperature and pressure. soln

3. If a molecule of neon gas travels at an average of 400 m/s at a given temperature, estimate the average speed of a molecule of butane gas, C_{4}H_{10}, at the same temperature. soln

4. Compare diffusion with effusion.

5. List the following gases in order of increasing average molecular velocity at 25^{0} C:

a) H_{2}O;

b) He

c) HCl

d) BrF

e) NO_{2}