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Problem 62
Consider a mixture of two gases, A and B, confined in a closed vessel. A quantity of a third gas, C, is added to the same vessel at the same temperature. How does the addition of gas C affect the following: (a) the partial pressure of gas A?
- A mixture containing 0.50 mol H2(g), 1.00 mol O2(g), and 3.50 mol N2(g) is confined in a 25.0-L vessel at 25 °C. Calculate the partial pressure of H2, O2, and N2.
Problem 63
- A deep-sea diver uses a gas cylinder with a volume of 10.0 L and a content of 51.2 g of O2 and 32.6 g of He. Calculate the partial pressure of each gas and the total pressure if the temperature of the gas is 19 °C.
Problem 64
Problem 65
The atmospheric concentration of CO2 gas is presently 407 ppm (parts per million, by volume; that is, 407 L of every 106 L of the atmosphere are CO2). What is the mole fraction of CO2 in the atmosphere?.
- A plasma-screen TV contains thousands of tiny cells filled with a mixture of Xe, Ne, and He gases that emits light of specific wavelengths when a voltage is applied. A particular plasma cell, 0.900 mm * 0.300 mm * 10.0 mm, contains 4% Xe in a 1:1 Ne:He mixture at a total pressure of 66.66 kPa. Calculate the number of Ne atoms in the cell and state the assumptions you need to make in your calculation.
Problem 66
- A piece of dry ice (solid carbon dioxide) with a mass of 20.0 g is placed in a 25.0-L vessel that already contains air at 50.66 kPa and 25 °C. After the carbon dioxide has totally sublimed, what is the partial pressure of the resultant CO2 gas, and the total pressure in the container at 25 °C?
Problem 67
- A sample of 5.00 mL of diethylether 1C2H5OC2H5, density = 0.7134 g>mL2 is introduced into a 6.00-L vessel that already contains a mixture of N2 and O2, whose partial pressures are PN2 = 21.08 kPa and PO2 = 76.1 kPa. The temperature is held at 35.0 °C, and the diethylether totally evaporates. (b) Calculate the total pressure in the container.
Problem 68
- A rigid vessel containing a 3:1 mol ratio of carbon dioxide and water vapor is held at 200 °C where it has a total pressure of 202.7 kPa. If the vessel is cooled to 10 °C so that all of the water vapor condenses, what is the pressure of carbon dioxide? Neglect the volume of the liquid water that forms on cooling.
Problem 69
- At an underwater depth of 100 m, the pressure is 1.106 MPa. What should the partial pressure of oxygen be in the diving gas for the mole fraction of oxygen in the mixture to be 0.21, the same as in air?
Problem 71
Problem 72a1
(a) What are the mole fractions of O2 in a mixture of 15.08 g of O2, 8.17 g of N2, and 2.64 g of H2?
Problem 72a2
(a) What are the mole fractions of N2 in a mixture of 15.08 g of O2, 8.17 g of N2, and 2.64 g of H2?
Problem 72a3
(a) What are the mole fractions of H2 in a mixture of 15.08 g of O2, 8.17 g of N2, and 2.64 g of H2?
Problem 72b
(b) What is the partial pressure in atm of each component of this mixture if its held in a 15.50-L vessel at 15 °C?
- A quantity of N2 gas originally held at 531.96 kPa pressure in a 1.00-L container at 26 °C is transferred to a 12.5-L container at 20 °C. A quantity of O2 gas originally at 531.96 kPa and 26 °C in a 5.00-L container is transferred to this same container. What is the total pressure in the new container?
Problem 73
Problem 74a,b
A sample of 3.00 g of SO2(g) originally in a 5.00-L vessel at 21 °C is transferred to a 10.0-L vessel at 26 °C. A sample of 2.35 g of N2(g) originally in a 2.50-L vessel at 20 °C is transferred to this same 10.0-L vessel. (a) What is the partial pressure of SO2(g) in the larger container? (b) What is the partial pressure of N2(g) in this vessel?
Problem 74c
A sample of 3.00 g of SO2(g) originally in a 5.00-L vessel at 21 °C is transferred to a 10.0-L vessel at 26 °C. A sample of 2.35 g of N2(g) originally in a 2.50-L vessel at 20 °C is transferred to this same 10.0-L vessel. (c) What is the total pressure in the vessel?
Problem 75a
Determine whether each of the following changes will increase, decrease, or not affect the rate with which gas molecules collide with the walls of their container: (a) increasing the volume of the container (b) increasing the temperature (c) increasing the molar mass of the gas
Problem 76
Indicate which of the following statements regarding the kinetic-molecular theory of gases are correct. (a) The average kinetic energy of a collection of gas molecules at a given temperature is proportional to m1/2. (b) The gas molecules are assumed to exert no forces on each other. (c) All the molecules of a gas at a given temperature have the same kinetic energy. (d) The volume of the gas molecules is negligible in comparison to the total volume in which the gas is contained. (e) All gas molecules move with the same speed if they are at the same temperature.
- Radon (Rn) is the heaviest (and only radioactive) member of the noble gases. How much slower is the root-mean-square speed of Rn than He at 300 K?
Problem 77
Problem 78
You have an evacuated container of fixed volume and known mass and introduce a known mass of a gas sample. Measuring the pressure at constant temperature over time, you are surprised to see it slowly dropping. You measure the mass of the gas-filled container and find that the mass is what it should be—gas plus container—and the mass does not change over time, so you do not have a leak. Suggest an explanation for your observations.
Problem 79a
The temperature of a 5.00-L container of N2 gas is increased from 20 °C to 250 °C. If the volume is held constant, predict qualitatively how this change affects the following: (a) the average kinetic energy of the molecules.
Problem 79b,c,d
The temperature of a 5.00-L container of N2 gas is increased from 20 °C to 250 °C. If the volume is held constant, predict qualitatively how this change affects the following: (b) the rootmean-square speed of the molecules. (c) the strength of the impact of an average molecule with the container walls. (d) the total number of collisions of molecules with walls per second.
Problem 80a
Suppose you have two 1-L flasks, one containing N2 at STP, the other containing CH4 at STP. How do these systems compare with respect to (a) number of molecules?
Problem 80b
Suppose you have two 1-L flasks, one containing N2 at STP, the other containing CH4 at STP. How do these systems compare with respect to (b) density?
Problem 80c
Suppose you have two 1-L flasks, one containing N2 at STP, the other containing CH4 at STP. How do these systems compare with respect to (c) average kinetic energy of the molecules?
- Place the following gases in order of increasing average molecular speed at 25 °C: O2, Ar, CO, HCl, CH4.
Problem 81
Problem 81b
(b) Calculate the rms speed of NF3 molecules at 25 °C.
Problem 81c
(c) Calculate the most probable speed of an ozone molecule in the stratosphere, where the temperature is 270 K.
Problem 82c1
(c) Calculate the most probable speeds of CO molecules at 300 K.
Problem 82c2
(c) Calculate the most probable speeds of Cl2 molecules at 300 K.