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Problem 135a,b
Pakistan's K2 is the world's second-tallest mountain, with an altitude of 28,251 ft. Its base camp, where climbers stop to acclimate, is located about 16,400 ft above sea level. (a) Approximate atmospheric pressure P at different altitudes is given by the equation P = e-h/7000, where P is in atmospheres and h is the altitude in meters. What is the approximate atmospheric pressure in mm Hg at K2 base camp? (b) What is the atmospheric pressure in mm Hg at the summit of K2?
- 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 Hg
Problem 1
- 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 atm
Problem 2
- 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 L
Problem 3
- 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 g
Problem 4
- 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 L
Problem 5
- A certain nonmetal reacts with hydrogen at 440 °C to form a poisonous, foul-smelling gas. A sample with a mass of 6.618 g was found to have a volume of 2.00 L at 25.0 °C and 1.00 atm. What is the molecular weight of the gas? (LO 10.6) (a) 67.9 g/mol (b) 162 g/mol (c) 80.9 g/mol (d) 193.6 g/mol
Problem 6
- 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 7
- A sample of ammonia (NH3) gas is completely decomposed to nitrogen and hydrogen over a heated iron catalyst. If the total pressure of the mixture of N2 and H2 is 1.80 atm, what is the partial pressure of N2? (LO 10.7) (a) 1.35 atm (b) 0.45 atm (c) 0.90 atm (d) 0.63 atm
Problem 8
- 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 9
- 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
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
- 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/s
Problem 11
- 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/mol
Problem 12
- 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 13
- 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.
Problem 23
(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.
- 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 31
- 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 32
- 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 34
- 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 35
- Why do gases exert pressure?
Problem 36
- Why are gases so much more compressible than solids or liquids?
Problem 37
- Atmospheric pressure at the top of Pikes Peak in Colorado is approximately 480 mm Hg. Convert this value to atmospheres and to pascals.
Problem 38
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 39c
Carry out the following conversions: (c) 0.0382 mm Hg to Pa
