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Problem 72b
Hydrogen gas can be prepared by reaction of zinc metal with aqueous HCl: Zn(s) + 2 HCl(aq) ¡ ZnCl2(aq) + H2(g) (b) How many grams of zinc would you start with if you wanted to prepare 5.00 L of H2 at 350 mm Hg and 30.0 °C?
- Ammonium nitrate can decompose explosively when heated according to the equation 2 NH4NO31s2¡2 N21g2 + 4 H2O1g2 + O21g2 How many liters of gas would be formed at 450 °C and 1.00 atm pressure by explosion of 450 g of NH4NO3?
Problem 73
- The reaction of sodium peroxide 1Na2O22 with CO2 is used in space vehicles to remove CO2 from the air and generate O2 for breathing: 2 Na2O21s2 + 2 CO21g2¡2 Na2CO31s2 + O21g2 (a) Assuming that air is breathed at an average rate of 4.50 L/min (25 °C; 735 mm Hg) and that the concentration of CO2 in expelled air is 3.4% by volume, how many grams of CO2 are produced in 24 h?
Problem 74
Problem 75b
Titanium(III) chloride, a substance used in catalysts for preparing polyethylene, is made by high-temperature reaction of TiCl4 vapor with H2: 2 TiCl4(g) + H2(g) → 2 TiCl3(s) + 2 HCl(g) (b) How many liters of HCl gas at STP will result from the reaction described in part (a)?
- A typical high-pressure tire on a bicycle might have a volume of 365 mL and a pressure of 7.80 atm at 25 °C. Suppose the rider filled the tire with helium to minimize weight. What is the mass of the helium in the tire?
Problem 76
- One of the largest sources of SO2 to the atmosphere is coal-fired power plants. Calculate the volume of SO2 in liters produced by burning 1 kg of coal that contains 2% sulfur. Assume all the sulfur is converted to SO2.
Problem 78
- A special gas mixture used in bacterial growth chambers contains 1.00% by weight CO2 and 99.0% O2. What is the partial pressure in atmospheres of each gas at a total pressure of 0.977 atm?
Problem 82
- A gas mixture for use in some lasers contains 5.00% by weight HCl, 1.00% H2, and 94% Ne. The mixture is sold in cylinders that have a volume of 49.0 L and a pressure of 13,800 kPa at 210 °C. What is the partial pressure in kilopascals of each gas in the mixture?
Problem 83
- What is the mole fraction of each gas in the mixture described in Problem 10.83?
Problem 84
- A mixture of Ar and N2 gases has a density of 1.413 g/L at STP. What is the mole fraction of each gas?
Problem 85
Problem 86a
A mixture of 14.2 g of H2 and 36.7 g of Ar is placed in a 100.0-L container at 290 K. (a) What is the partial pressure of H2 in atmospheres?
Problem 86b
A mixture of 14.2 g of H2 and 36.7 g of Ar is placed in a 100.0-L container at 290 K. (b) What is the partial pressure of Ar in atmospheres?
- A 20.0-L flask contains 0.776 g of He and 3.61 g of CO2 at 300 K. (a) What is the partial pressure of He in mm Hg?
Problem 87
Problem 89a
Chlorine gas was first prepared in 1774 by the oxidation of NaCl with MnO2: 2 NaCl(s) + 2 H2SO4(l) + MnO2(s) → Na2SO4(s) + MnSO4(s) + 2 H2O(g) + Cl2(g) Assume that the gas produced is saturated with water vapor at a partial pressure of 28.7 mm Hg and that it has a volume of 0.597 L at 27 °C and 755 mm Hg pressure. (a) What is the mole fraction of Cl2 in the gas?
Problem 89b
Chlorine gas was first prepared in 1774 by the oxidation of NaCl with MnO2: 2 NaCl(s) + 2 H2SO4(l) + MnO2(s) → Na2SO4(s) + MnSO4(s) + 2 H2O(g) + Cl2(g) Assume that the gas produced is saturated with water vapor at a partial pressure of 28.7 mm Hg and that it has a volume of 0.597 L at 27 °C and 755 mm Hg pressure. (b) How many grams of NaCl were used in the experiment, assuming complete reaction?
Problem 90a
Natural gas is a mixture of hydrocarbons, primarily methane 1CH42 and ethane 1C2H62. A typical mixture might have Xmethane = 0.915 and Xethane = 0.085. Let's assume that we have a 15.50 g sample of natural gas in a volume of 15.00 L at a temperature of 20.00 °C. (a) How many total moles of gas are in the sample?
Problem 90b
Natural gas is a mixture of hydrocarbons, primarily methane (CH4) and ethane (C2H6). A typical mixture might have Xmethane = 0.915 and Xethane = 0.085. Let's assume that we have a 15.50 g sample of natural gas in a volume of 15.00 L at a temperature of 20.00 °C. (b) What is the pressure of the sample in atmospheres?
Problem 90c
Natural gas is a mixture of hydrocarbons, primarily methane (CH4) and ethane (C2H6). A typical mixture might have Xmethane = 0.915 and Xethane = 0.085. Let's assume that we have a 15.50 g sample of natural gas in a volume of 15.00 L at a temperature of 20.00 °C. (c) What is the partial pressure of each component in the sample in atmospheres?
Problem 91a
Gaseous compound Q contains only xenon and oxygen. When 0.100 g of Q is placed in a 50.0-mL steel vessel at 0 °C the pressure is 0.229 atm. (a) What is the molar mass of Q, and what is a likely formula?
Problem 91b
Gaseous compound Q contains only xenon and oxygen. When 0.100 g of Q is placed in a 50.0-mL steel vessel at 0 °C the pressure is 0.229 atm. (b) When the vessel and its contents are warmed to 100 °C, Q decomposes into its constituent elements. What is the total pressure, and what are the partial pressures of xenon and oxygen in the container?
- What are the basic assumptions of the kinetic–molecular theory?
Problem 92
Problem 93
What is the difference between heat and temperature?
- The average temperature at an altitude of 20 km is 220 K. What is the average speed in m/s of an N2 molecule at this altitude?
Problem 94
- Calculate the average speed of a nitrogen molecule in m/s on a hot day in summer 1T = 37 °C2 and on a cold day in winter 1T = -25 °C2.
Problem 95
- At what temperature (°C) will xenon atoms have the same average speed that Br2 molecules have at 20° C?
Problem 96
- At what temperature does the average speed of an oxygen molecule equal that of an airplane moving at 580 mph?
Problem 97
- Which has a higher average speed, H2 at 150 K or He at 375 °C?
Problem 98
- Which has a higher average speed, a Ferrari at 145 mph or a gaseous UF6 molecule at 145 °C?
Problem 99
- A big-league fastball travels at about 45 m/s. At what temperature (°C) do helium atoms have this same average speed?
Problem 100
- Traffic on the German autobahns reaches speeds of up to 230 km/h. At what temperature (°C) do oxygen molecules have this same average speed?
Problem 101