Chapter 13

List two conditions under which a gas is least likely to behave ideally.

What units must be used to express the temperature in the equation for the ideal gas law? Explain.

Home Fuel Propane \(\left(C_{3} H_{8}\right)\) is a gas commonly used as a home fuel for cooking and heating. a. Calculate the volume that 0.540 mol of propane occupies at STP. b. Think about the size of this volume and the amount of propane that it contains. Why do you think propane is usually liquefied before it is transported?

Careers in Chemistry A physical chemist measured the lowest pressure achieved in a laboratory - about \(1.0 \times 10^{-15} mm\) Hg. How many molecules of gas are present in a \(1.00-L\) sample at that pressure if the sample's temperature is \(22.0^{\circ} C ?\)

Calculate the number of moles of \(O^{2}\) gas held in a sealed, \(2.00-L\) tank at 3.50 \(\mathrm{atm}\) and \(25.0^{\circ} C .\) How many moles would be in the tank if the temperature was raised to \(49.0^{\circ} C\) and the pressure remained constant?

Perfumes Geraniol is a compound found in rose oil that is used in perfumes. What is the molar mass of geraniol if its vapor has a density of 0.480 g/L at a temperature of 260.0°C and a pressure of 0.140 atm?

Find the volume that 42 g of carbon monoxide gas occupies at STP.

What is the density of a sample of nitrogen gas \(\left(N_{2}\right)\) that exerts a pressure of 5.30 \(\mathrm{atm}\) in a \(3.50-L\) container at \(125^{\circ} C ?\)

How many moles of helium gas (He) would be required to fill a 22-L container at a temperature of 35°C and a pressure of 3.1 atm?

Before a reaction, two gases share a container at a temperature of 200 K. After the reaction, the product is in the same container at a temperature of 400 K. If both V and \(P\) are constant, what must be true of \(n?\)

Why must an equation be balanced before using it to determine the volumes of gases involved in a reaction?

It is not necessary to consider temperature and pressure when using a balanced equation to determine relative gas volume. Why?

What information do you need to solve a volume-mass problem that involves gases?

Explain why the coefficients in a balanced chemical equation represent not only molar amounts but also relative volumes for gases.

Do the coefficients in a balanced chemical equation represent volume ratios for solids and liquids? Explain.

A 6.5-L sample of hydrogen sulfide is treated with a catalyst to promote the reaction shown below. $$2 H_{2} \mathrm{S}(\mathrm{g})+O_{2}(\mathrm{g}) \rightarrow 2 H_{2} O(\mathrm{g})+2 \mathrm{S}(\mathrm{s})$$ If the \(\mathrm{H}_{2} \mathrm{S}\) reacts completely at 2.0 atm and 290 \(\mathrm{K},\) how much water vapor, in grams, is produced?

To produce 15.4 L of nitrogen dioxide at 310 K and 2.0 atm, how many liters of nitrogen gas and oxygen gas are required?

Use the reaction shown below to answer these questions. $$2 CO(\mathrm{g})+2 NO(\mathrm{g}) \rightarrow N_{2}(\mathrm{g})+2 CO_{2}(\mathrm{g})$$ a. What is the volume ratio of carbon monoxide to carbon dioxide in the balanced equation? b. If 42.7 g of CO is reacted completely at STP, what volume of \(N_{2}\) gas will be produced?

When heated, solid potassium chlorate \(\left(KClO_{3}\right)\) decomposes to form solid potassium chloride and oxygen gas. If 20.8 \(\mathrm{g}\) of potassium chlorate decomposes, how many liters of oxygen gas will form at STP?

Acetylene The gas acetylene, often used for welding, burns according to the following equation. $$2 C_{2} H_{2}(\mathrm{g})+5 O_{2}(\mathrm{g}) \rightarrow 2 H_{2} O(\mathrm{g})+4 CO_{2}(\mathrm{g})$$ If you have a \(10.0-L\) tank of acetylene at \(25.0^{\circ} C\) and 1.00 atm pressure, how many moles of \(CO_{2}\) will be produced if you burn all the acetylene in the tank?

Gaseous methane \(\left(CH_{4}\right)\) undergoes complete combustion by reacting with oxygen gas to form carbon dioxide and water vapor. a. Write a balanced equation for this reaction. b. What is the volume ratio of methane to water in this reaction?

Television Determine the pressure inside a television picture tube with a volume of 3.50 \(L\) that contains \(2.00 \times 10^{-5}\) g of nitrogen gas at \(22.0^{\circ} C .\)

Determine how many liters 8.80 g of carbon dioxide gas would occupy at: a. STP b. 160°C and 3.00 atm c. 288 K and 118 kPa

Oxygen Consumption If 5.00 L of hydrogen gas, measured at a temperature of 20.0°C and a pressure of 80.1 kPa, is burned in excess oxygen to form water, what mass of oxygen will be consumed? Assume temperature and pressure remain constant.

A fixed amount of oxygen gas is held in a 1.00-L tank at a pressure of 3.50 atm. The tank is connected to an empty 2.00-L tank by a tube with a valve. After this valve has been opened and the oxygen is allowed to flow freely between the two tanks at a constant temperature, what is the final pressure in the system?

If 2.33 L of propane at 24°C and 67.2 kPa is completely burned in excess oxygen, how many moles of carbon dioxide will be produced?

Apply An oversized helium balloon in a floral shop must have a volume of at least 3.8 L to rise. When 0.1 mol is added to the empty balloon, its volume is 2.8 L. How many grams of He must be added to make it rise? Assume constant \(T\) and \(P.\)

Calculate A toy manufacturer uses tetra fluoroethane \(\left(C_{2} H_{2} F_{4}\right)\) at high temperatures to fill plastic molds for toys. a. What is the density (in \(\mathrm{g} / L )\) of \(C_{2} H_{2} F_{4}\) at STP? b. Find the molecules per liter of \(C_{2} H_{2} F_{4}\) at \(220^{\circ} C\) and 1.0 \(\mathrm{atm} .\)

Analyze A solid brick of dry ice \(\left(CO_{2}\right)\) weighs 0.75 kg. Once the brick has fully sublimated into \(\left(CO_{2}\right)\) gas, what would its volume be at STP?

Apply Calculate the pressure of \(4.67 \times 10^{22}\) molecules of \(CO\) gas mixed with \(2.87 \times 10^{24}\) molecules of \(N_{2}\) gas in a 6.00 -L container at \(34.8^{\circ} C .\)

Analyze When nitroglycerin \(\left(C_{3} H_{5} N_{3} O_{9}\right)\) explodes, it decomposes into the following gases: \(CO_{2}, N_{2}, NO\) , and \(H_{2} O\) . If 239 \(\mathrm{g}\) of nitroglycerin explodes, what volume will the mixture of gaseous products occupy at 1.00 \(\mathrm{atm}\) pressure and \(2678^{\circ} C ?\)

Apply What is the numerical value of the ideal gas constant \((\mathrm{R})\) in \(\frac{cm^{3} . Pa_{}}{K \text { -mol }} ?\)

Infer At very high pressures, will the ideal gas law calculate a pressure that is higher or lower than the actual pressure exerted by a sample of gas? How will the calculated pressure compare to the actual pressure at low temperatures? Explain your answers.

Convert each mass measurement to its equivalent in kilograms. (Chapter 2) \(\begin{array}{ll}{\text { a. } 247 \mathrm{g}} & {\text { c. } 7.23 \mathrm{mg}} \\ {\text { b. } 53 \mathrm{mg}} & {\text { d. } 975 \mathrm{mg}}\end{array}\)

Write the electron configuration for each atom. (Chapter 5) \(\begin{array}{ll}{\text { a. iodine }} & {\text { d. krypton }} \\ {\text { b. boron }} & {\text { e. calcium }} \\ {\text { c. chromium }} & {\text { f. cadmium }}\end{array}\)

For each element, tell how many electrons are in each energy level and write the electron dot structure. (Chapter 5) \(\begin{array}{ll}{\text { a. Kr }} & {\text { d. B }} \\ {\text { b. Sr }} & {\text { e. Br }} \\ {\text { c. } P} & {\text { f. Se }}\end{array}\)

How many atoms of each element are present in five formula units of calcium permanganate? (Chapter 7)

You are given two clear, colorless aqueous solutions. One solution contains an ionic compound, and one contains a covalent compound. How could you determine which is an ionic solution and which is a covalent solution? (Chapter 8)

Write a balanced equation for the following reactions. (Chapter 9) a. Zinc displaces silver in silver chloride. b. Sodium hydroxide and sulfuric acid react to form sodium sulfate and water

Terephthalic acid is an organic compound used in the formation of polyesters. It contains 57.8% C, 3.64% H, and 38.5% O. The molar mass is approximately 166 g/mol. What is the molecular formula of terephthalic acid? (Chapter 10)

Hot-Air Balloons Many early balloonists dreamed of completing a trip around the world in a hot-air balloon, a goal not achieved until 1999. Write about what you imagine a trip in a balloon would be like, including a description of how manipulating air temperature would allow you to control altitude.

Scuba Investigate and explain the function of the regulators on the air tanks used by scuba divers.

Explain how the percent yield of ammonia is affected by pressure and temperature.