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Problem 45
A piece of dry ice (solid carbon dioxide) with a mass of 28.8 g sublimes (converts from solid to gas) into a large balloon. Assuming that all of the carbon dioxide ends up in the balloon, what is the volume of the balloon at 22 °C and a pressure of 742 mmHg?
Problem 46
A 1.0-L container of liquid nitrogen is kept in a closet measuring 1.0 m by 1.0 m by 2.0 m. Assuming that the container is completely full, that the temperature is 25.0 °C, and that the atmospheric pressure is 1.0 atm, calculate the percent (by volume) of air that is displaced if all of the liquid nitrogen evaporates. (Liquid nitrogen has a density of 0.807 g/mL.)
- A wine-dispensing system uses argon canisters to pressurize and preserve wine in the bottle. An argon canister for the system has a volume of 55.0 mL and contains 26.0 g of argon. When the argon is released from the canister, it expands to fill the wine bottle. How many 750.0-mL wine bottles can be purged with the argon in the canister at a pressure of 1.20 atm and a temperature of 295 K? Assuming ideal gas behavior, what is the pressure in the canister at 295 K?
Problem 47
- Cyclists sometimes use pressurized carbon dioxide inflators to inflate a bicycle tire in the event of a flat. These inflators use metal cartridges that contain 16.0 g of carbon dioxide. At 298 K, to what pressure (in psi) can the carbon dioxide in the cartridge inflate a 3.45-L mountain bike tire? (Note: Assume that atmospheric pressure is 14.7 psi; the gauge pressure is the total pressure minus the atmospheric pressure.)
Problem 48
Problem 49
Which gas sample has the greatest pressure? Assume that all the samples are at the same temperature. Explain.
Problem 50
This picture represents a sample of gas at a pressure of 1 atm, a volume of 1 L, and a temperature of 25 °C. Draw a similar picture showing what would happen to the sample if the volume were reduced to 0.5 L and the temperature were increased to 250 °C. What would happen to the pressure?
Problem 51
Aerosol cans carry clear warnings against incineration because of the high pressures that can develop upon heating. Suppose that a can contains a residual amount of gas at a pressure of 755 mmHg and a temperature of 25 °C. What would the pressure be if the can were heated to 1155 °C?
Problem 52
A sample of nitrogen gas in a 1.75-L container exerts a pressure of 1.35 atm at 25 °C. What is the pressure if the volume of the container is maintained constant and the temperature is raised to 355 °C?
Problem 53
Use the molar volume of a gas at STP to determine the volume (in L) occupied by 33.6 g of neon at STP.
Problem 54
Use the molar volume of a gas at STP to calculate the density (in g/L) of nitrogen gas at STP.
Problem 55
What is the density (in g/L) of hydrogen gas at 20.0 °C and a pressure of 1655 psi?
Problem 56
A sample of N2O gas has a density of 2.85 g/L at 298 K. What is the pressure of the gas (in mmHg)?
Problem 57
A 248-mL gas sample has a mass of 0.433 g at a pressure of 745 mmHg and a temperature of 28 °C. What is the molar mass of the gas?
Problem 58
A 113-mL gas sample has a mass of 0.171 g at a pressure of 721 mmHg and a temperature of 32 °C. What is the molar mass of the gas?
Problem 59
A sample of gas has a mass of 38.8 mg. Its volume is 224 mL at a temperature of 55 °C and a pressure of 886 torr. Find the molar mass of the gas.
Problem 60
A sample of gas has a mass of 0.555 g. Its volume is 117 mL at a temperature of 85 °C and a pressure of 753 mmHg. Find the molar mass of the gas.
Problem 61
A gas mixture contains each of the following gases at the indicated partial pressures: N2, 215 torr; O2, 102 torr; and He, 117 torr. What is the total pressure of the mixture? What mass of each gas is present in a 1.35-L sample of this mixture at 25.0 °C?
Problem 62
A gas mixture with a total pressure of 745 mmHg contains each of the following gases at the indicated partial pressures: CO2, 125 mmHg; Ar, 214 mmHg; and O2, 187 mmHg. The mixture also contains helium gas. What is the partial pressure of the helium gas? What mass of helium gas is present in a 12.0-L sample of this mixture at 273 K?
Problem 63
A 1.20-g sample of dry ice is added to a 755 mL flask containing nitrogen gas at a temperature of 25.0 °C and a pressure of 725 mmHg. The dry ice sublimes (converts from solid to gas), and the mixture returns to 25.0 °C. What is the total pressure in the flask?
Problem 64
A 275-mL flask contains pure helium at a pressure of 752 torr. A second flask with a volume of 475 mL contains pure argon at a pressure of 722 torr. If we connect the two flasks through a stopcock and we open the stopcock, what is the partial pressure of argon?
Problem 65
A gas mixture contains 1.25 g N2 and 0.85 g O2 in a 1.55 L container at 18 °C. Calculate the mole fraction and partial pressure of each component in the gas mixture.
Problem 66
What is the mole fraction of oxygen gas in air (see Table 5.3)? What volume of air contains 10.0 g of oxygen gas at 273 K and 1.00 atm?
Problem 67
The hydrogen gas formed in a chemical reaction is collected over water at 30.0 °C at a total pressure of 732 mmHg. What is the partial pressure of the hydrogen gas collected in this way? If the total volume of gas collected is 722 mL, what mass of hydrogen gas is collected?
Problem 68
The air in a bicycle tire is bubbled through water and collected at 25 °C. If the total volume of gas collected is 5.45 L at a temperature of 25 °C and a pressure of 745 torr, how many moles of gas were in the bicycle tire?
Problem 69
The zinc in a copper-plated penny will dissolve in hydrochloric acid if the copper coating is filed down in several spots (so that the hydrochloric acid can get to the zinc). The reaction between the acid and the zinc is 2 H+(aq) + Zn(s) → H2(g) + Zn2+(aq). When the zinc in a certain penny dissolves, the total volume of gas collected over water at 25 °C is 0.951 L at a total pressure of 748 mmHg. What mass of hydrogen gas is collected?
Problem 70
A heliox deep-sea diving mixture contains 2.0 g of oxygen to every 98.0 g of helium. What is the partial pressure of oxygen when this mixture is delivered at a total pressure of 8.5 atm?
Problem 71
Consider the chemical reaction: C(s) + H2O(g) → CO(g) + H2(g) How many liters of hydrogen gas are formed from the complete reaction of 15.7 g C? Assume that the hydrogen gas is collected at a pressure of 1.0 atm and a temperature of 355 K.
Problem 72
Consider the chemical reaction: 2 H2O(l) → 2 H2(g) + O2(g) What mass of H2O is required to form 1.4 L of O2 at a temperature of 315 K and a pressure of 0.957 atm?
Problem 73
CH3OH can be synthesized by the reaction: CO(g) + 2 H2(g) → CH3OH( g) What volume of H2 gas (in L), at 748 mmHg and 86 °C, is required to synthesize 25.8 g CH3OH? How many liters of CO gas, measured under the same conditions, are required?
Problem 74
Oxygen gas reacts with powdered aluminum according to the reaction: 4 Al(s) + 3 O2(g) → 2 Al2O3(s) What volume of O2 gas (in L), measured at 782 mmHg and 25 °C, completely reacts with 53.2 g Al?