Ch.10 - Gases: Their Properties & Behavior
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Problem 1
The recommended pressure for inflation of an automobile tire is 35 psi. What is the pressure in units of mm Hg? 11 atm = 14.7 psi; 1 atm = 760 mm Hg2 (LO 10.1) (a) 3.9 * 105 mm Hg (b) 0.68 mm Hg (c) 3.2 * 102 mm Hg (d) 1.8 * 103 mm HgProblem 2
What is the pressure of the gas inside the bulb (atm) if the outside pressure is 0.92 atm? (a) 1.1 atm (b) 2.6 atm (c) 0.22 atm (d) 0.70 atmProblem 3
Assume that you have a gas cylinder with a movable piston filled with oxygen. The initial conditions are T = 250 K, n = 0.140 mol O2, and P = 1.00 atm. If the initial volume is 1.0 L, what is the volume when the temperature is increased to 400 K and the pressure is decreased to 0.75 atm? (LO 10.3) (a) 2.1 L (b) 1.2 L (c) 0.83 L (d) 1.6 LProblem 4
Many laboratory gases are sold in steel cylinders with a volume of 43.8 L. What is the mass in grams of argon inside a cylinder whose pressure is 17,180 kPa at 20 °C? (LO 10.4) (a) 1.83 * 107 g (b) 1.81 * 105 g (c) 1.23 * 104 g (d) 122 gProblem 5
Propane gas 1C3H82 is often used as fuel in rural areas. How many liters of CO2 are formed at STP by the complete combustion of the propane in a container with a volume of 15.0 L and a pressure of 4.50 atm at 25.0 °C? The equation for the combustion of propane is: C3H81g2 + 5 O21g2¡3 CO21g2 + 4 H2O1l2 (LO 10.4, 10.5) (a) 61.8 L (b) 186 L (c) 20.6 L (d) 2.21 * 103 LProblem 7
Trimix is a gas mixture consisting of oxygen, helium, and nitrogen used for deep scuba dives. The helium is included to reduce the effects of nitrogen narcosis and oxygen toxicity that occur when too much nitrogen and oxygen dissolve in the blood. A tank of Trimix has a total pressure of 200 atm, and the partial pressure of He is 34 atm. What is the percent by volume of He in the tank? (LO 10.7) (a) 17% (b) 38% (c) 23% (d) 83%Problem 9
The apparatus shown consists of three bulbs connected by stopcocks. What is the pressure inside the system when the stopcocks are opened? Assume that the lines connecting the bulbs have zero volume and that the temperature remains constant. (LO 10.3, 10.7) (a) 1.10 atm (b) 1.73 atm (c) 4.14 atm (d) 1.41 atm
Problem 10
A mixture of chlorine, hydrogen, and oxygen gas is in a container at STP. Which curve represents oxygen gas? (LO 10.8) (a) Curve (a) (b) Curve (b) (c) Curve (c)
Problem 10.108c
Two 112-L tanks are filled with gas at 330 K. One contains 5.00 mol of Kr, and the other contains 5.00 mol of O2. Considering the assumptions of kinetic–molecular theory, rank the gases from low to high for each of the following properties.
(c) Average speed
Problem 10.109a
Two identical 732.0-L tanks each contain 212.0 g of gas at 293 K, with neon in one tank and nitrogen in the other. Based on the assumptions of kinetic–molecular theory, rank the gases from low to high for each of the following properties.
(a) Average speed
Problem 11
The coldest temperature recorded at ground level on Earth was -89.2 °C at the Vostok Station in Antarctica. What is the speed of a nitrogen molecule at this temperature? (LO 10.9) (a) 933 m/s (b) 40.2 m/s (c) 404 m/s (d) 12.8 m/sProblem 12
An unknown gas is found to diffuse through a porous membrane 2.92 times more slowly than H2. What is the molecular weight of the gas? (a) 17.0 g/mol (b) 5.84 g/mol (c) 8.52 g/molProblem 13
Identify the true statement about deviations from ideal gas behavior. (LO 10.12) (a) The attractive forces between gas particles cause the true volume of the sample to be larger than predicted by the ideal gas law. (b) The attractive forces between gas particles most influence the volume of a sample at low pressure. (c) The volume of the gas particles themselves most influences the volume of the sample at low pressure. (d) The volume of the gas particles themselves causes the true volume of the sample to be larger than predicted by the ideal gas law.Problem 23
A glass tube has one end in a dish of mercury and the other end closed by a stopcock. The distance from the surface of the mercury to the bottom of the stopcock is 850 mm. The apparatus is at 25 °C, and the mercury level in the tube is the same as that in the dish.
(a) Show on drawing (1) what the approximate level of mercury in the tube will be when the temperature of the entire apparatus is lowered from +25 °C to -25 °C.
Problem 26a
Assume that you have a sample of gas in a cylinder with a movable piston, as shown in the following drawing:
Redraw the apparatus to show what the sample will look like after (a) the temperature is increased from 300 K to 450 K at constant pressure
Problem 26b
Assume that you have a sample of gas in a cylinder with a movable piston, as shown in the following drawing:
Redraw the apparatus to show what the sample will look like after (b) the pressure is increased from 1 atm to 2 atm at constant temperature
Problem 26c
Assume that you have a sample of gas in a cylinder with a movable piston, as shown in the following drawing:
Redraw the apparatus to show what the sample will look like after (c) the temperature is decreased from 300 K to 200 K and the pressure is decreased from 3 atm to 2 atm.
Problem 31
Show the approximate level of the movable piston in drawings (a), (b), and (c) after the indicated changes have been made to the gas.
Problem 32
A 1:1 mixture of helium (red) and argon (blue) at 300 K is portrayed below on the left. Draw the same mixture when the temperature is lowered to 150 K.Problem 34
Yet another common measure of pressure is the unit pounds per square inch (psi). How many pounds per square inch correspond to 1.00 atm? To 1.00 mm Hg?Problem 35
If the density of water is 1.00 g/mL and the density of mercury is 13.6 g/mL, how high a column of water in meters can be supported by standard atmospheric pressure? By 1 bar?Problem 36
Why do gases exert pressure?Problem 38
Atmospheric pressure at the top of Pikes Peak in Colorado is approximately 480 mm Hg. Convert this value to atmospheres and to pascals.Problem 39a
Carry out the following conversions: (a) 352 torr to kPa
Problem 39b
Carry out the following conversions: (b) 0.255 atm to mm Hg
Problem 40
What is the pressure in millimeters of mercury inside a container of gas connected to a mercury-filled open-end manometer of the sort shown in Figure 10.5 when the level in the arm connected to the container is 17.6 cm lower than the level in the arm open to the atmosphere and the atmospheric pressure reading outside the apparatus is 754.3 mm Hg?Problem 41
What is the pressure in atmospheres inside a container of gas connected to a mercury-filled open-end manometer when the level in the arm connected to the container is 28.3 cm higher than the level in the arm open to the atmosphere and the atmospheric pressure reading outside the apparatus is 1.021 atm?Problem 42
Assume that you have an open-end manometer filled with ethyl alcohol 1density = 0.7893 g>mL at 20 °C2 rather than mercury 1density = 13.546 g>mL at 20 °C2. What is the pressure in pascals if the level in the arm open to the atmosphere is 55.1 cm higher than the level in the arm connected to the gas sample and the atmospheric pressure reading is 752.3 mm Hg?Problem 45
The surface temperature of Venus is about 1050 K, and the pressure is about 75 Earth atmospheres. Assuming that these conditions represent a Venusian 'STP,' what is the standard molar volume in liters of a gas on Venus?Problem 46
Calculate the average molecular weight of air from the data given in Table 10.1.
