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- A 500 mL incandescent light bulb is filled with 1.5 * 10-5 mol of xenon to minimize the rate of evaporation of the tungsten filament. What is the pressure of xenon in the light bulb at 25 _x001F_C?
Problem 1
Problem 2b
You have a sample of gas in a container with a movable piston, such as the one in the drawing. (b) Redraw the container to show what it might look like if the external pressure on the piston is increased from 101.3 kPa to 202.7 kPa while the temperature is kept constant.
- Which of the following statements best explains why nitrogen gas at STP is less dense than Xe gas at STP? (a) Because Xe is a noble gas, there is less tendency for the Xe atoms to repel one another, so they pack more densely in the gaseous state. (b) Xe atoms have a higher mass than N2 molecules. Because both gases at STP have the same number of molecules per unit volume, the Xe gas must be denser. (c) The Xe atoms are larger than N2 molecules and thus take up a larger fraction of the space occupied by the gas. (d) Because the Xe atoms are much more massive than the N2 molecules, they move more slowly and thus exert less upward force on the gas container and make the gas denser.
Problem 5
Problem 6b
The apparatus shown here has two gas-filled containers and one empty container, all attached to a hollow horizontal tube. Assume that the containers are of equal volume and ignore the volume of the connecting tube. Which gas has the greater partial pressure after the valves are opened?
- 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 (d) the rate of effusion through a pinhole leak?
Problem 8
Problem 9b
Consider the following graph. (b) If A and B refer to the same gas at two different temperatures, which represents the higher temperature?
Problem 10c
Consider the following samples of gases:
If the three samples are all at the same temperature, rank them with respect to (c) density
Problem 11
A thin glass tube 1 m long is filled with Ar gas at 101.3 kPa, and the ends are stoppered with cotton plugs as shown below. HCl gas is introduced at one end of the tube, and simultaneously NH3 gas is introduced at the other end. When the two gases diffuse through the cotton plugs down the tube and meet, a white ring appears due to the formation of NH4Cl1s2. At which location—a, b, or c—do you expect the ring to form?
- Determine the percentage composition of the substance.
Problem 12
Problem 12a
The graph below shows the change in pressure as the temperature increases for a 1-mol sample of a gas confined to a 1-L container. The four plots correspond to an ideal gas and three real gases: CO2, N2, and Cl2. (a) At room temperature, all three real gases have a pressure less than the ideal gas. Which van der Waals constant, a or b, accounts for the influence intermolecular forces have in lowering the pressure of a real gas?
Problem 12b
The graph below shows the change in pressure as the temperature increases for a 1-mol sample of a gas confined to a 1-L container. The four plots correspond to an ideal gas and three real gases: CO2, N2, and Cl2. (b) Use the van der Waals constants in Table 10.3 to match the labels in the plot (A, B, and C) with the respective gases 1CO2, N2, and Cl22.
- Are you more likely to see the density of a gas reported in g/mL, g/L, or kg/cm³?
Problem 14
Problem 14b
(b) Which units are appropriate for expressing atmospheric pressures, N, Pa, atm, kg/m2?
Problem 14c
(c) Which is most likely to be a gas at room temperature and ordinary atmospheric pressure, F2, Br2, K2O?
Problem 15a
A person weighing 75 kg is standing on a threelegged stool. The stool momentarily tilts so that the entire weight is on one foot. If the contact area of each foot is 5.0 cm2, calculate the pressure exerted on the underlying surface in (a) bars
Problem 15b
A person weighing 75 kg is standing on a threelegged stool. The stool momentarily tilts so that the entire weight is on one foot. If the contact area of each foot is 5.0 cm2, calculate the pressure exerted on the underlying surface in (b) atmospheres
Problem 15c
A person weighing 75 kg is standing on a threelegged stool. The stool momentarily tilts so that the entire weight is on one foot. If the contact area of each foot is 5.0 cm2, calculate the pressure exerted on the underlying surface in (c) pounds per square inch
Problem 17a
(a) How high in meters must a column of ethanol be to exert a pressure equal to that of a 100-mm column of mercury? The density of ethanol is 0.79 g/mL, whereas that of mercury is 13.6 g/mL. Assume that the density of the water is 1.00 5 1.00 3 103 kg/m3. The gravitational constant is 9.81 m/s2, and 1 Pa 5 1 kg/ms2.
Problem 17b
(b) What pressure, in atmospheres, is exerted on the body of a diver if she is 10 m below the surface of the water when the atmospheric pressure is 100 kPa? Assume that the density of the water is 1.00 5 1.00 3 103 kg/m3. The gravitational constant is 9.81 m/s2, and 1 Pa 5 1 kg/ms2
Problem 18a
(a) The compound 1-iodododecane is a nonvolatile liquid with a density of 1.20 g>mL. The density of mercury is 13.6 g>mL. What do you predict for the height of a barometer column based on 1-iodododecane, when the atmospheric pressure is 749 torr?
Problem 19b
The highest barometric pressure ever recorded was 823.7 torr at Agata in Siberia, Russia on December 31, 1968. Convert this pressure to (b) mm Hg
Problem 19c
The highest barometric pressure ever recorded was 823.7 torr at Agata in Siberia, Russia on December 31, 1968. Convert this pressure to (c) pascals.
Problem 19d
The highest barometric pressure ever recorded was 823.7 torr at Agata in Siberia, Russia on December 31, 1968. Convert this pressure to (d) bars.
Problem 19e
The highest barometric pressure ever recorded was 823.7 torr at Agata in Siberia, Russia on December 31, 1968. Convert this pressure to (e) psi.
Problem 20d
Perform the following conversions: (d) 1.323 * 105 Pa to atmospheres
- In the United States, barometric pressures are generally reported in inches of mercury (in. Hg). On a beautiful summer day in Chicago, the barometric pressure is 30.45 in. Hg. (a) Convert this pressure to torr.
Problem 21
Problem 22a
Hurricane Wilma of 2005 is the most intense hurricane on record in the Atlantic basin, with a low-pressure reading of 882 mbar (millibars). Convert this reading into (a) atmospheres.
Problem 22b
Hurricane Wilma of 2005 is the most intense hurricane on record in the Atlantic basin, with a low-pressure reading of 882 mbar (millibars). Convert this reading into (b) torr.
Problem 22c
Hurricane Wilma of 2005 is the most intense hurricane on record in the Atlantic basin, with a low-pressure reading of 882 mbar (millibars). Convert this reading into (c) inches of Hg.
Problem 23a
If the atmospheric pressure is 0.995 atm, what is the pressure of the enclosed gas in each of the three cases depicted in the drawing? Assume that the gray liquid is mercury. (i)