Solved: Hydrogen azide, HN3, decomposes on heating by the

Consider the following apparatus: a test tube covered with a nonpermeableelastic membrane inside a container that is closed witha cork. A syringe goes through the cork.a. As you push down on the syringe, how does the membranecovering the test tube change?b. You stop pushing the syringe but continue to hold it down.In a few seconds, what happens to the membrane?

Figure 5.2 shows a picture of a barometer. Which of the followingstatements is the best explanation of how this barometer works?a. Air pressure outside the tube causes the mercury to move in thetube until the air pressure inside and outside the tube is equal.b. Air pressure inside the tube causes the mercury to move in thetube until the air pressure inside and outside the tube is equal.c. Air pressure outside the tube counterbalances the weight ofthe mercury in the tube.d. Capillary action of the mercury causes the mercury to go upthe tube.e. The vacuum that is formed at the top of the tube holds up themercury.Justify your choice, and for the choices you did not pick, explainwhat is wrong with them. Pictures help!

The barometer below shows the level of mercury at a given atmosphericpressure. Fill all the other barometers with mercuryfor that same atmospheric pressure. Explain your answer.

As you increase the temperature of a gas in a sealed, rigid container,what happens to the density of the gas? Would the resultsbe the same if you did the same experiment in a container witha piston at constant pressure? (See Figure 5.17.)

A diagram in a chemistry book shows a magnified view of aflask of air as follows:What do you suppose is between the dots (the dots represent airmolecules)?a. airb. dustc. pollutantsd. oxygene. nothing

If you put a drinking straw in water, place your finger over theopening, and lift the straw out of the water, some water stays inthe straw. Explain.

A chemistry student relates the following story: I noticed mytires were a bit low and went to the gas station. As I was fillingthe tires, I thought about the kinetic molecular theory (KMT). Inoticed the tires because the volume was low, and I realized thatI was increasing both the pressure and volume of the tires.Hmmm, I thought, that goes against what I learned in chemistry,where I was told pressure and volume are inversely proportional.What is the fault in the logic of the chemistry studentin this situation? Explain why we think pressure and volume tobe inversely related (draw pictures and use the KMT).

Chemicals X and Y (both gases) react to form the gas XY, but ittakes a bit of time for the reaction to occur. Both X and Y areplaced in a container with a piston (free to move), and you notethe volume. As the reaction occurs, what happens to the volumeof the container? (See Fig. 5.18.)

Which statement best explains why a hot-air balloon rises whenthe air in the balloon is heated?a. According to Charless law, the temperature of a gas isdirectly related to its volume. Thus the volume of the balloonincreases, making the density smaller. This lifts the balloon.b. Hot air rises inside the balloon, and this lifts the balloon.c. The temperature of a gas is directly related to its pressure.The pressure therefore increases, and this lifts the balloon.d. Some of the gas escapes from the bottom of the balloon, thusdecreasing the mass of gas in the balloon. This decreases thedensity of the gas in the balloon, which lifts the balloon.e. Temperature is related to the root mean square velocity of thegas molecules. Thus the molecules are moving faster, hittingthe balloon more, and thus lifting the balloon.Justify your choice, and for the choices you did not pick, explainwhat is wrong with them.

Draw a highly magnified view of a sealed, rigid container filledwith a gas. Then draw what it would look like if you cooled thegas significantly but kept the temperature above the boiling pointof the substance in the container. Also draw what it would looklike if you heated the gas significantly. Finally, draw what eachsituation would look like if you evacuated enough of the gas todecrease the pressure by a factor of 2.

If you release a helium balloon, it soars upward and eventuallypops. Explain this behavior.

If you have any two gases in different containers that are thesame size at the same pressure and same temperature, what istrue about the moles of each gas? Why is this true?

Explain the following seeming contradiction: You have twogases, A and B, in two separate containers of equal volume andat equal pressure and temperature. Therefore, you must have thesame number of moles of each gas. Because the two temperaturesare equal, the average kinetic energies of the two samplesare equal. Therefore, since the energy given such a system willbe converted to translational motion (that is, move the molecules),the root mean square velocities of the two are equal, andthus the particles in each sample move, on average, with the samerelative speed. Since A and B are different gases, they each musthave a different molar mass. If A has higher molar mass than B,the particles of A must be hitting the sides of the container withmore force. Thus the pressure in the container of gas A must behigher than that in the container with gas B. However, one ofour initial assumptions was that the pressures were equal.

You have a balloon covering the mouth of a flask filled with airat 1 atm. You apply heat to the bottom of the flask until the volumeof the balloon is equal to that of the flask.a. Which has more air in it, the balloon or the flask? Or do bothhave the same amount? Explain.b. In which is the pressure greater, the balloon or the flask? Oris the pressure the same? Explain.

How does Daltons law of partial pressures help us with ourmodel of ideal gases? That is, what postulates of the kinetic moleculartheory does it support?

At room temperature, water is a liquid with a molar volume of18 mL. At 105_C and 1 atm pressure, water is a gas and has amolar volume of over 30 L. Explain the large difference in molarvolumes.

If a barometer were built using water (d _ 1.0 g/cm3) instead ofmercury (d _ 13.6 g/cm3), would the column of water be higherthan, lower than, or the same as the column of mercury at1.00 atm? If the level is different, by what factor? Explain.

A bag of potato chips is packed and sealed in Los Angeles,California, and then shipped to Lake Tahoe, Nevada, during skiseason. It is noticed that the volume of the bag of potato chipshas increased upon its arrival in Lake Tahoe. What externalconditions would most likely cause the volume increase?

Boyles law can be represented graphically in several ways.Which of the following plots does not correctly represent Boyleslaw (assuming constant T and n)? Explain.

As weather balloons rise from the earths surface, the pressure ofthe atmosphere becomes less, tending to cause the volume of theballoons to expand. However, the temperature is much lower inthe upper atmosphere than at sea level. Would this temperatureeffect tend to make such a balloon expand or contract? Weatherballoons do, in fact, expand as they rise. What does this tell you?

Which noble gas has the smallest density at STP? Explain.

Consider two different containers, each filled with 2 moles ofNe(g). One of the containers is rigid and has constant volume.The other container is flexible (like a balloon) and is capable ofchanging its volume to keep the external pressure and internalpressure equal to each other. If you raise the temperature in bothcontainers, what happens to the pressure and density of the gasinside each container? Assume a constant external pressure.

Do all the molecules in a 1-mol sample of CH4(g) have the samekinetic energy at 273 K? Do all molecules in a 1-mol sample ofN2(g) have the same velocity at 546 K? Explain.

Consider the following samples of gases at the same temperature.Arrange each of these samples in order from lowest to highest:a. pressureb. average kinetic energyc. densityd. root mean square velocityNote: Some samples of gases may have equal values for theseattributes. Assume the larger containers have a volume twice thevolume of the smaller containers and assume the mass of an argonatom is twice the mass of a neon atom.

As NH3(g) is decomposed into nitrogen gas and hydrogen gas atconstant pressure and temperature, the volume of the product gasescollected is twice the volume of NH3 reacted. Explain. As NH3(g)is decomposed into nitrogen gas and hydrogen gas at constantvolume and temperature, the total pressure increases by somefactor. Why the increase in pressure and by what factor does thetotal pressure increase when reactants are completely convertedinto products? How do the partial pressures of the product gasescompare to each other and to the initial pressure of NH3?

Which of the following statements is (are) true? For the falsestatements, correct them.a. At constant temperature, the lighter the gas molecules, thefaster the average velocity of the gas molecules.b. At constant temperature, the heavier the gas molecules, thelarger the average kinetic energy of the gas molecules.c. A real gas behaves most ideally when the container volumeis relatively large and the gas molecules are moving relativelyquickly.d. As temperature increases, the effect of interparticle interactionson gas behavior is increased.e. At constant V and T, as gas molecules are added into a container,the number of collisions per unit area increases resultingin a higher pressure.f. The kinetic molecular theory predicts that pressure is inverselyproportional to temperature at constant volume and mol of gas.

Freon-12 (CF2Cl2) is commonly used as the refrigerant in centralhome air conditioners. The system is initially charged to apressure of 4.8 atm. Express this pressure in each of the followingunits (1 atm _ 14.7 psi).a. mm Hg b. torr c. Pa d. psi

A gauge on a compressed gas cylinder reads 2200 psi (poundsper square inch; 1 atm _14.7 psi). Express this pressure in eachof the following units.a. standard atmospheresb. megapascals (MPa)c. torr

A sealed-tube manometer (as shown below) can be used to measurepressures below atmospheric pressure. The tube above themercury is evacuated. When there is a vacuum in the flask, themercury levels in both arms of the U-tube are equal. If a gaseoussample is introduced into the flask, the mercury levels are different.The difference h is a measure of the pressure of the gasinside the flask. If h is equal to 6.5 cm, calculate the pressure inthe flask in torr, pascals, and atmospheres.Gash

If the sealed-tube manometer in Exercise 29 had a height differenceof 20.0 inches between the mercury levels, what is thepressure in the flask in torr and atmospheres?

A diagram for an open-tube manometer is shown below.If the flask is open to the atmosphere, the mercury levels areequal. For each of the following situations where a gas is containedin the flask, calculate the pressure in the flask in torr, atmospheres,and pascals.c. Calculate the pressures in the flask in parts a and b (in torr)if the atmospheric pressure is 635 torr.

a. If the open-tube manometer in Exercise 31 contains a nonvolatilesilicone oil (density _ 1.30 g/cm3) instead of mercury(density _ 13.6 g/cm3), what are the pressures in the flask asshown in parts a and b in torr, atmospheres, and pascals?b. What advantage would there be in using a less dense fluidthan mercury in a manometer used to measure relatively smalldifferences in pressure?

A particular balloon is designed by its manufacturer to be inflatedto a volume of no more than 2.5 L. If the balloon is filledwith 2.0 L of helium at sea level, is released, and rises to an altitudeat which the atmospheric pressure is only 500. mm Hg,will the balloon burst? (Assume temperature is constant.)

A balloon is filled to a volume of 7.00 _ 102 mL at a temperatureof 20.0_C. The balloon is then cooled at constant pressureto a temperature of 1.00 _ 102 K. What is the final volume ofthe balloon?

An 11.2-L sample of gas is determined to contain 0.50 mol ofN2. At the same temperature and pressure, how many moles ofgas would there be in a 20.-L sample?

Consider the following chemical equation.If 25.0 mL of NO2 gas is completely converted to N2O4 gas underthe same conditions, what volume will the N2O4 occupy?

Complete the following table for an ideal gas.2NO21g2!N2O41g2a. 5.00 2.00 155_Cb. 0.300 2.00 155 Kc. 4.47 25.0 2.01d. 2.25 10.5 75_C

Complete the following table for an ideal gas.a. 7.74 _ 103 Pa 12.2 mL 25_Cb. 43.0 mL 0.421 mol 223 Kc. 455 torr 4.4 _ 10_2 mol 331_Cd. 745 mm Hg 11.2 L 0.401 mol

Suppose two 200.0-L tanks are to be filled separately with thegases helium and hydrogen. What mass of each gas is needed toproduce a pressure of 135 atm in its respective tank at 24_C?

A flask that can withstand an internal pressure of 2500 torr, butno more, is filled with a gas at 21.0_C and 758 torr and heated.At what temperature will it burst?

A 2.50-L container is filled with 175 g argon.a. If the pressure is 10.0 atm, what is the temperature?b. If the temperature is 225 K, what is the pressure?

A person accidentally swallows a drop of liquid oxygen, O2(l),which has a density of 1.149 g/mL. Assuming the drop has avolume of 0.050 mL, what volume of gas will be produced inthe persons stomach at body temperature (37_C) and a pressureof 1.0 atm?

A gas sample containing 1.50 mol at 25_C exerts a pressure of400. torr. Some gas is added to the same container and the temperatureis increased to 50._C. If the pressure increases to 800.torr, how many moles of gas were added to the container? Assumea constant-volume container.

A bicycle tire is filled with air to a pressure of 100. psi at atemperature of 19_C. Riding the bike on asphalt on a hot dayincreases the temperature of the tire to 58_C. The volume of thetire increases by 4.0%. What is the new pressure in the bicycletire?

Consider two separate gas containers at the following conditions:How is the pressure in container B related to the pressure in containerA?

A container is filled with an ideal gas to a pressure of 40.0 atmat 0_C.a. What will be the pressure in the container if it is heated to45_C?b. At what temperature would the pressure be 1.50 _ 102 atm?c. At what temperature would the pressure be 25.0 atm?

An ideal gas is contained in a cylinder with a volume of 5.0 _102 mL at a temperature of 30._C and a pressure of 710. torr.The gas is then compressed to a volume of 25 mL, and thetemperature is raised to 820._C. What is the new pressure ofthe gas?

A compressed gas cylinder contains 1.00 _ 103 g of argon gas.The pressure inside the cylinder is 2050. psi (pounds per squareinch) at a temperature of 18_C. How much gas remains in thecylinder if the pressure is decreased to 650. psi at a temperatureof 26_C?

A sealed balloon is filled with 1.00 L of helium at 23_C and1.00 atm. The balloon rises to a point in the atmosphere wherethe pressure is 220. torr and the temperature is _31_C. Whatis the change in volume of the balloon as it ascends from 1.00 atmto a pressure of 220. torr?

A hot-air balloon is filled with air to a volume of 4.00 _ 103m3at 745 torr and 21_C. The air in the balloon is then heated to62_C, causing the balloon to expand to a volume of 4.20 _103m3.What is the ratio of the number of moles of air in the heated balloonto the original number of moles of air in the balloon? (Hint:Openings in the balloon allow air to flow in and out. Thus thepressure in the balloon is always the same as that of theatmosphere.)

Consider the following reaction:It takes 2.00 L of pure oxygen gas at STP to react completelywith a certain sample of aluminum. What is the mass of aluminumreacted?

A student adds 4.00 g of dry ice (solid CO2) to an empty balloon.What will be the volume of the balloon at STP after all thedry ice sublimes (converts to gaseous CO2)?

Air bags are activated when a severe impact causes a steel ballto compress a spring and electrically ignite a detonator cap. Thiscauses sodium azide (NaN3) to decompose explosively accordingto the following reaction:What mass of NaN3(s) must be reacted to inflate an air bag to70.0 L at STP?

Concentrated hydrogen peroxide solutions are explosivelydecomposed by traces of transition metal ions (such as Mnor Fe):What volume of pure O2(g), collected at 27_C and 746 torr, wouldbe generated by decomposition of 125 g of a 50.0% by masshydrogen peroxide solution? Ignore any water vapor that may bepresent.

In 1897 the Swedish explorer Andre tried to reach the NorthPole in a balloon. The balloon was filled with hydrogen gas. Thehydrogen gas was prepared from iron splints and diluted sulfuricacid. The reaction isThe volume of the balloon was 4800 m3 and the loss ofhydrogen gas during filling was estimated at 20.%. What massof iron splints and 98% (by mass) H2SO4 were needed toensure the complete filling of the balloon? Assume a temperatureof 0_C, a pressure of 1.0 atm during filling, and100% yield.

Sulfur trioxide, SO3, is produced in enormous quantities eachyear for use in the synthesis of sulfuric acid.What volume of O2(g) at 350._C and a pressure of 5.25 atm isneeded to completely convert 5.00 g of sulfur to sulfur trioxide?

Consider the reaction between 50.0 mL of liquid methyl alcohol,CH3OH (density _ 0.850 g/mL), and 22.8 L of O2 at 27_Cand a pressure of 2.00 atm. The products of the reaction areCO2(g) and H2O(g). Calculate the number of moles of H2Oformed if the reaction goes to completion.

Urea (H2NCONH2) is used extensively as a nitrogen source infertilizers. It is produced commercially from the reaction of ammoniaand carbon dioxide:Ammonia gas at 223_C and 90. atm flows into a reactor at a rateof 500. L/min. Carbon dioxide at 223_C and 45 atm flows intothe reactor at a rate of 600. L/min. What mass of urea is producedper minute by this reaction assuming 100% yield?

Hydrogen cyanide is prepared commercially by the reaction ofmethane, CH4(g), ammonia, NH3(g), and oxygen, O2(g), at hightemperature. The other product is gaseous water.a. Write a chemical equation for the reaction.b. What volume of HCN(g) can be obtained from 20.0 L CH4(g),20.0 L NH3(g), and 20.0 L O2(g)? The volumes of all gasesare measured at the same temperature and pressure.

Methanol, CH3OH, can be produced by the following reaction:Hydrogen at STP flows into a reactor at a rate of 16.0 L/min.Carbon monoxide at STP flows into the reactor at a rate of25.0 L/min. If 5.30 g of methanol is produced per minute, whatis the percent yield of the reaction?

An unknown diatomic gas has a density of 3.164 g/L at STP.What is the identity of the gas?

A compound has the empirical formula CHCl. A 256-mL flask,at 373 K and 750. torr, contains 0.800 g of the gaseous compound.Give the molecular formula.

Uranium hexafluoride is a solid at room temperature, but it boilsat 56_C. Determine the density of uranium hexafluoride at 60._Cand 745 torr.

Given that a sample of air is made up of nitrogen, oxygen,and argon in the mole fractions 78% N2, 21% O2, and 1.0%Ar, what is the density of air at standard temperature andpressure?

A piece of solid carbon dioxide, with a mass of 7.8 g, is placedin a 4.0-L otherwise empty container at 27_C. What is the pressurein the container after all the carbon dioxide vaporizes? If7.8 g solid carbon dioxide were placed in the same container butit already contained air at 740 torr, what would be the partialpressure of carbon dioxide and the total pressure in the containerafter the carbon dioxide vaporizes?

A mixture of 1.00 g H2 and 1.00 g He is placed in a 1.00-L containerat 27_C. Calculate the partial pressure of each gas and thetotal pressure.

Consider the flasks in the following diagram. What are the finalpartial pressures of H2 and N2 after the stopcock between thetwo flasks is opened? (Assume the final volume is 3.00 L.) Whatis the total pressure (in torr)?

Consider the flask apparatus in Exercise 67, which now contains2.00 L of H2 at a pressure of 360. torr and 1.00 L of N2 at anunknown pressure. If the total pressure in the flasks is 320. torrafter the stopcock is opened, determine the initial pressure of N2in the 1.00-L flask.

The partial pressure of CH4(g) is 0.175 atm and that of O2(g) is0.250 atm in a mixture of the two gases.a. What is the mole fraction of each gas in the mixture?b. If the mixture occupies a volume of 10.5 L at 65_C, calculatethe total number of moles of gas in the mixture.c. Calculate the number of grams of each gas in the mixture.

A 1.00-L gas sample at 100._C and 600. torr contains 50.0% heliumand 50.0% xenon by mass. What are the partial pressuresof the individual gases?

Small quantities of hydrogen gas can be prepared in thelaboratory by the addition of aqueous hydrochloric acid tometallic zinc.Typically, the hydrogen gas is bubbled through water for collectionand becomes saturated with water vapor. Suppose 240.mL of hydrogen gas is collected at 30._C and has a total pressureof 1.032 atm by this process. What is the partial pressureof hydrogen gas in the sample? How many grams of zinc musthave reacted to produce this quantity of hydrogen? (The vaporpressure of water is 32 torr at 30_C.)

Helium is collected over water at 25_C and 1.00 atm total pressure.What total volume of gas must be collected to obtain 0.586 gof helium? (At 25_C the vapor pressure of water is 23.8 torr.)

At elevated temperatures, sodium chlorate decomposes toproduce sodium chloride and oxygen gas. A 0.8765-g sample ofimpure sodium chlorate was heated until the production of oxygengas ceased. The oxygen gas collected over water occupied57.2 mL at a temperature of 22_C and a pressure of 734 torr.Calculate the mass percent of NaClO3 in the original sample.(At 22_C the vapor pressure of water is 19.8 torr.)

Xenon and fluorine will react to form binary compounds whena mixture of these two gases is heated to 400_C in a nickelreaction vessel. A 100.0-mL nickel container is filled with xenonand fluorine, giving partial pressures of 1.24 atm and 10.10 atm,respectively, at a temperature of 25_C. The reaction vessel isheated to 400_C to cause a reaction to occur and then cooled toa temperature at which F2 is a gas and the xenon fluoridecompound produced is a nonvolatile solid. The remaining F2 gasis transferred to another 100.0-mL nickel container, where thepressure of F2 at 25_C is 7.62 atm. Assuming all of the xenonhas reacted, what is the formula of the product?

Hydrogen azide, HN3, decomposes on heating by the followingunbalanced reaction:If 3.0 atm of pure HN3(g) is decomposed initially, what is thefinal total pressure in the reaction container? What are the partialpressures of nitrogen and hydrogen gas? Assume the volumeand temperature of the reaction container are constant.

Some very effective rocket fuels are composed of lightweightliquids. The fuel composed of dimethylhydrazine [(CH3)2N2H2]mixed with dinitrogen tetroxide was used to power the LunarLander in its missions to the moon. The two components reactaccording to the following equation:If 150 g of dimethylhydrazine reacts with excess dinitrogentetroxide and the product gases are collected at 27_C in an evacuated250-L tank, what is the partial pressure of nitrogen gasproduced and what is the total pressure in the tank assuming thereaction has 100% yield?

Calculate the average kinetic energies of CH4 and N2 moleculesat 273 K and 546 K.

A 100.-L flask contains a mixture of methane, CH4, and argonat 25_C. The mass of argon present is 228 g and the mole fractionof methane in the mixture is 0.650. Calculate the total kineticenergy of the gaseous mixture.

Calculate the root mean square velocities of CH4 and N2 moleculesat 273 K and 546 K.

Consider separate 1.0-L samples of He(g) and UF6(g), both at1.00 atm and containing the same number of moles. What ratioof temperatures for the two samples would produce the sameroot mean square velocity?

Consider a 1.0-L container of neon gas at STP. Will the averagekinetic energy, average velocity, and frequency of collisionsof gas molecules with the walls of the container increase,decrease, or remain the same under each of the followingconditions?a. The temperature is increased to 100_C.b. The temperature is decreased to _50_C.c. The volume is decreased to 0.5 L.d. The number of moles of neon is doubled.

Consider two gases, A and B, each in a 1.0-L container with bothgases at the same temperature and pressure. The mass of gas Ain the container is 0.34 g and the mass of gas B in the containeris 0.48 g.a. Which gas sample has the most molecules present? Explain.b. Which gas sample has the largest average kinetic energy?Explain.c. Which gas sample has the fastest average velocity? Explain.d. How can the pressure in the two containers be equal to eachother since the larger gas B molecules collide with the containerwalls more forcefully?

Consider three identical flasks filled with different gases.Flask A: CO at 760 torr and 0_CFlask B: N2 at 250 torr and 0_CFlask C: H2 at 100 torr and 0_Ca. In which flask will the molecules have the greatest averagekinetic energy?b. In which flask will the molecules have the greatest averagevelocity?

Consider separate 1.0-L gaseous samples of H2, Xe, Cl2, and O2all at STP.a. Rank the gases in order of increasing average kinetic energy.b. Rank the gases in order of increasing average velocity.c. How can separate 1.0-L samples of O2 and H2 each have thesame average velocity?

Freon-12 is used as a refrigerant in central home air conditioners.The rate of effusion of Freon-12 to Freon-11 (molar mass _137.4 g/mol) is 1.07:1. The formula of Freon-12 is one of thefollowing: CF4, CF3Cl, CF2Cl2, CFCl3, or CCl4. Which formulais correct for Freon-12?

The rate of effusion of a particular gas was measured and foundto be 24.0 mL/min. Under the same conditions, the rate of effusionof pure methane (CH4) gas is 47.8 mL/min. What is the molarmass of the unknown gas?

One way of separating oxygen isotopes is by gaseous diffusionof carbon monoxide. The gaseous diffusion process behaves likean effusion process. Calculate the relative rates of effusion of12C16O, 12C17O, and 12C18O. Name some advantages and disadvantagesof separating oxygen isotopes by gaseous diffusion ofcarbon dioxide instead of carbon monoxide.

It took 4.5 minutes for 1.0 L helium to effuse through a porousbarrier. How long will it take for 1.0 L Cl2 gas to effuse underidentical conditions?

Calculate the pressure exerted by 0.5000 mol N2 in a 1.0000-Lcontainer at 25.0_Ca. using the ideal gas law.b. using the van der Waals equation.c. Compare the results.

Calculate the pressure exerted by 0.5000 mol N2 in a 10.000-Lcontainer at 25.0_Ca. using the ideal gas law.b. using the van der Waals equation.c. Compare the results.d. Compare the results with those in Exercise 89.

Use the data in Table 5.4 to calculate the partial pressure of Hein dry air assuming that the total pressure is 1.0 atm. Assuminga temperature of 25_C, calculate the number of He atoms per cubiccentimeter.

A 1.0-L sample of air is collected at 25_C at sea level (1.00 atm).Estimate the volume this sample of air would have at an altitudeof 15 km (see Fig. 5.30).

Write reactions to show how nitric and sulfuric acids are producedin the atmosphere.

Write reactions to show how the nitric and sulfuric acids in acidrain react with marble and limestone. (Both marble and limestoneare primarily calcium carbonate.)

Draw a qualitative graph to show how the first property varieswith the second in each of the following (assume 1 mol of anideal gas and T in kelvins).a. PV versus V with constant Tb. P versus T with constant Vc. T versus V with constant Pd. P versus V with constant Te. P versus 1_V with constant Tf. PV_T versus P

At STP, 1.0 L Br2 reacts completely with 3.0 L F2, producing2.0 L of a product. What is the formula of the product? (All substancesare gases.)

A form of Boyles law is PV _ k (at constant T and n). Table5.1 contains actual data from pressurevolume experimentsconducted by Robert Boyle. The value of k in mostexperiments is 14.1 _ 102 in Hg in3. Express k in units ofatm L. In Sample Exercise 5.3, k was determined for NH3 atvarious pressures and volumes. Give some reasons why the kvalues differ so dramatically between Sample Exercise 5.3 andTable 5.1.

An ideal gas at 7_C is in a spherical flexible container having aradius of 1.00 cm. The gas is heated at constant pressure to 88_C.Determine the radius of the spherical container after the gas isheated. (Volume of a sphere _ 4_3r 3.)

A 2.747-g sample of manganese metal is reacted with excessHCl gas to produce 3.22 L of H2(g) at 373 K and 0.951 atmand a manganese chloride compound (MnClx). What is theformula of the manganese chloride compound produced in thereaction?

Equal moles of hydrogen gas and oxygen gas are mixed in aflexible reaction vessel and then sparked to initiate the formationof gaseous water. Assuming that the reaction goes to completion,what is the ratio of the final volume of the gas mixtureto the initial volume of the gas mixture if both volumes are measuredat the same temperature and pressure?

A 15.0-L tank is filled with H2 to a pressure of 2.00 _ 102 atm.How many balloons (each 2.00 L) can be inflated to a pressureof 1.00 atm from the tank? Assume that there is no temperaturechange and that the tank cannot be emptied below 1.00 atmpressure.

A spherical glass container of unknown volume contains heliumgas at 25_C and 1.960 atm. When a portion of the helium is withdrawnand adjusted to 1.00 atm at 25_C, it is found to have avolume of 1.75 cm3. The gas remaining in the first containershows a pressure of 1.710 atm. Calculate the volume of the sphericalcontainer.

A 2.00-L sample of O2(g) was collected over water at a totalpressure of 785 torr and 25_C. When the O2(g) was dried (watervapor removed), the gas had a volume of 1.94 L at 25_C and785 torr. Calculate the vapor pressure of water at 25_C.

A 20.0-L stainless steel container was charged with 2.00 atm ofhydrogen gas and 3.00 atm of oxygen gas. A spark ignited themixture, producing water. What is the pressure in the tank at25_C? at 125_C?

Metallic molybdenum can be produced from the mineral molybdenite,MoS2. The mineral is first oxidized in air to molybdenumtrioxide and sulfur dioxide. Molybdenum trioxide is thenreduced to metallic molybdenum using hydrogen gas. The balancedequations areCalculate the volumes of air and hydrogen gas at 17_C and 1.00atm that are necessary to produce 1.00 _ 103 kg of pure molybdenumfrom MoS2. Assume air contains 21% oxygen by volumeand assume 100% yield for each reaction.

Nitric acid is produced commercially by the Ostwald process. Inthe first step ammonia is oxidized to nitric oxide:Assume this reaction is carried out in the apparatus diagramedbelow.The stopcock between the two reaction containers is opened, andthe reaction proceeds using proper catalysts. Calculate the partialpressure of NO after the reaction is complete. Assume 100%yield for the reaction, assume the final container volume is3.00 L, and assume the temperature is constant.

In the Mthode Champenoise, grape juice is fermented in awine bottle to produce sparkling wine. The reaction isFermentation of 750. mL grape juice (density _ 1.0 g/cm3) isallowed to take place in a bottle with a total volume of 825 mLuntil 12% by volume is ethanol (C2H5OH). Assuming that theCO2 is insoluble in H2O (actually, a wrong assumption), whatwould be the pressure of CO2 inside the wine bottle at 25_C?(The density of ethanol is 0.79 g/cm3.)

One of the chemical controversies of the nineteenth century concernedthe element beryllium (Be). Berzelius originally claimedthat beryllium was a trivalent element (forming Be3_ ions) andthat it gave an oxide with the formula Be2O3. This resulted ina calculated atomic mass of 13.5 for beryllium. In formulatinghis periodic table, Mendeleev proposed that beryllium wasdivalent (forming Be2_ ions) and that it gave an oxide with theformula BeO. This assumption gives an atomic mass of 9.0. In1894, A. Combes (Comptes Rendus 1894, p. 1221) reactedberyllium with the anion C5H7O2_ and measured the densityof the gaseous product. Combess data for two different experimentsare as follows:If beryllium is a divalent metal, the molecular formula of theproduct will be Be(C5H7O2)2; if it is trivalent, the formula willbe Be(C5H7O2)3. Show how Combess data help to confirm thatberyllium is a divalent metal.

The nitrogen content of organic compounds can be determinedby the Dumas method. The compound in question is first reactedby passage over hot CuO(s):The product gas is then passed through a concentrated solutionof KOH to remove the CO2. After passage through the KOH solution,the gas contains N2 and is saturated with water vapor. Ina given experiment a 0.253-g sample of a compound produced31.8 mL N2 saturated with water vapor at 25_C and 726 torr.What is the mass percent of nitrogen in the compound? (Thevapor pressure of water at 25_C is 23.8 torr.)

A compound containing only C, H, and N yields the following data.i. Complete combustion of 35.0 mg of the compound produced33.5 mg of CO2 and 41.1 mg of H2O.ii. A 65.2-mg sample of the compound was analyzed fornitrogen by the Dumas method (see Exercise 109), giving35.6 mL of N2 at 740. torr and 25_C.iii. The effusion rate of the compound as a gas was measuredand found to be 24.6 mL/min. The effusion rate of argon gas,under identical conditions, is 26.4 mL/min.What is the molecular formula of the compound?

An organic compound contains C, H, N, and O. Combustion of0.1023 g of the compound in excess oxygen yielded 0.2766 g ofCO2 and 0.0991 g of H2O. A sample of 0.4831 g of the compoundwas analyzed for nitrogen by the Dumas method (see Exercise109). At STP, 27.6 mL of dry N2 was obtained. In a thirdexperiment, the density of the compound as a gas was found tobe 4.02 g/L at 127_C and 256 torr. What are the empirical andmolecular formulas of the compound?

Consider the following diagram:Container A (with porous walls) is filled with air at STP. It isthen inserted into a large enclosed container (B), which is thenflushed with H2(g). What will happen to the pressure inside containerA? Explain your answer.

Without looking at tables of values, which of the following gaseswould you expect to have the largest value of the van der Waalsconstant b: H2, N2, CH4, C2H6, or C3H8? From the values in Table5.3 for the van der Waals constant a for the gases H2, CO2, N2,and CH4, predict which of these gas molecules show the strongestintermolecular attractions.

An important process for the production of acrylonitrile (C3H3N)is given by the following reaction:A 150.-L reactor is charged to the following partial pressuresat 25_C:What mass of acrylonitrile can be produced from this mixture(Mpa _ 106 Pa)?

A chemist weighed out 5.14 g of a mixture containing unknownamounts of BaO(s) and CaO(s) and placed the sample in a 1.50-Lflask containing CO2(g) at 30.0_C and 750. torr. After the reactionto form BaCO3(s) and CaCO3(s) was completed, the pressure ofCO2(g) remaining was 230. torr. Calculate the mass percentagesof CaO(s) and BaO(s) in the mixture.

A mixture of chromium and zinc weighing 0.362 g was reactedwith an excess of hydrochloric acid. After all the metalsin the mixture reacted, 225 mL of dry hydrogen gas wascollected at 27_C and 750. torr. Determine the mass percentZn in the metal sample. [Zinc reacts with hydrochloric acidto produce zinc chloride and hydrogen gas; chromium reactswith hydrochloric acid to produce chromium(III) chloride andhydrogen gas.]

Consider a sample of a hydrocarbon (a compound consisting ofonly carbon and hydrogen) at 0.959 atm and 298 K. Upon combustingthe entire sample in oxygen, you collect a mixture ofgaseous carbon dioxide and water vapor at 1.51 atm and 375 K.This mixture has a density of 1.391 g/L and occupies a volumefour times as large as that of the pure hydrocarbon. Determinethe molecular formula of the hydrocarbon.

You have an equimolar mixture of the gases SO2 and O2, alongwith some He, in a container fitted with a piston. The density ofthis mixture at STP is 1.924 g/L. Assume ideal behavior andconstant temperature and pressure.a. What is the mole fraction of He in the original mixture?b. The SO2 and O2 react to completion to form SO3. What is thedensity of the gas mixture after the reaction is complete?

Methane (CH4) gas flows into a combustion chamber at a rateof 200. L/min at 1.50 atm and ambient temperature. Air is addedto the chamber at 1.00 atm and the same temperature, and thegases are ignited.a. To ensure complete combustion of CH4 to CO2(g) and H2O(g),three times as much oxygen as is necessary is reacted. Assumingair is 21 mole percent O2 and 79 mole percent N2,calculate the flow rate of air necessary to deliver the requiredamount of oxygen.b. Under the conditions in part a, combustion of methanewas not complete as a mixture of CO2(g) and CO(g) wasproduced. It was determined that 95.0% of the carbon inthe exhaust gas was present in CO2. The remainder was presentas carbon in CO. Calculate the composition of theexhaust gas in terms of mole fraction of CO, CO2, O2, N2,and H2O. Assume CH4 is completely reacted and N2 isunreacted.

A steel cylinder contains 5.00 mol of graphite (pure carbon) and5.00 mol of O2. The mixture is ignited and all the graphite reacts.Combustion produces a mixture of CO gas and CO2 gas.After the cylinder has cooled to its original temperature, it isfound that the pressure of the cylinder has increased by 17.0%.Calculate the mole fractions of CO, CO2, and O2 in the finalgaseous mixture.

The total mass that can be lifted by a balloon is given by the differencebetween the mass of air displaced by the balloon and themass of the gas inside the balloon. Consider a hot-air balloonthat approximates a sphere 5.00 m in diameter and contains airheated to 65_C. The surrounding air temperature is 21_C. Thepressure in the balloon is equal to the atmospheric pressure,which is 745 torr.a. What total mass can the balloon lift? Assume that the averagemolar mass of air is 29.0 g/mol. (Hint: Heated air is less densethan cool air.)b. If the balloon is filled with enough helium at 21_C and 745torr to achieve the same volume as in part a, what total masscan the balloon lift?c. What mass could the hot-air balloon in part a lift if it were onthe ground in Denver, Colorado, where a typical atmosphericpressure is 630. torr?

You have a sealed, flexible balloon filled with argon gas. Theatmospheric pressure is 1.00 atm and the temperature is25_C. The air has a mole fraction of nitrogen of 0.790, the restbeing oxygen.a. Explain why the balloon would float when heated. Make sureto discuss which factors change and which remain constant,and why this matters. Be complete.b. Above what temperature would you heat the balloon so thatit would float?

You have a helium balloon at 1.00 atm and 25_C. You want tomake a hot-air balloon with the same volume and same lift asthe helium balloon. Assume air is 79.0% nitrogen, 21.0% oxygenby volume. The lift of a balloon is given by the difference betweenthe mass of air displaced by the balloon and the mass ofgas inside the balloon.a. Will the temperature in the hot-air balloon have to be higheror lower than 25_C? Explain.b. Calculate the temperature of the air required for the hot-airballoon to provide the same lift as the helium balloon at 1.00atm and 25_C. Assume atmospheric conditions are 1.00 atmand 25_C.

We state that the ideal gas law tends to hold best at low pressuresand high temperatures. Show how the van der Waals equationsimplifies to the ideal gas law under these conditions.

Atmospheric scientists often use mixing ratios to express the concentrationsof trace compounds in air. Mixing ratios are oftenexpressed as ppmv (parts per million volume):On a recent autumn day, the concentration of carbon monoxidein the air in downtown Denver, Colorado, reached 3.0 _ 102ppmv. The atmospheric pressure at that time was 628 torr, andthe temperature was 0_C.a. What was the partial pressure of CO?b. What was the concentration of CO in molecules per cubiccentimeter?

Nitrogen gas (N2) reacts with hydrogen gas (H2) to form ammoniagas (NH3). You have nitrogen and hydrogen gases in a15.0-L container fitted with a movable piston (the piston allowsthe container volume to change so as to keep the pressure constantinside the container). Initially the partial pressure of eachreactant gas is 1.00 atm. Assume the temperature is constant andthat the reaction goes to completion.a. Calculate the partial pressure of ammonia in the container afterthe reaction has reached completion.b. Calculate the volume of the container after the reaction hasreached completion.

In the presence of nitric acid, UO2_ undergoes a redox process.It is converted to UO22_ and nitric oxide (NO) gas is producedaccording to the following unbalanced equation:NO3_1aq2 _ UO2_1aq2!NO1g2 _ UO22_1aq2If 2.55 _ 102 mL of NO(g) is isolated at 29_C and 1.5 atm, whatamount (moles) of UO2_ was used in the reaction?

Silane, SiH4, is the silicon analogue of methane, CH4. It isprepared industrially according to the following equations:a. If 156 mL of HSiCl3 (d _ 1.34 g/mL) is isolated when 15.0 Lof HCl at 10.0 atm and 35_C is used, what is the percent yieldof HSiCl3?b. When 156 mL of HSiCl3 is heated, what volume of SiH4 at10.0 atm and 35_C will be obtained if the percent yield of thereaction is 93.1%?

Solid thorium(IV) fluoride has a boiling point of 1680_C. Whatis the density of a sample of gaseous thorium(IV) fluoride at itsboiling point under a pressure of 2.5 atm in a 1.7-L container?Which gas will effuse faster at 1680_C, thorium(IV) fluoride oruranium(III) fluoride? How much faster?

Natural gas is a mixture of hydrocarbons, primarily methane(CH4) and ethane (C2H6). A typical mixture might have_methane_ 0.915 and _ethane_ 0.085. What are the partial pressuresof the two gases in a 15.00-L container of natural gas at20._C and 1.44 atm? Assuming complete combustion of bothgases in the natural gas sample, what is the total mass of waterformed?

Use the following information to identify element A and compoundB, then answer questions a and b.An empty glass container has a mass of 658.572 g. It has amass of 659.452 g after it has been filled with nitrogen gas at apressure of 790. torr and a temperature of 15_C. When the containeris evacuated and refilled with a certain element (A) at apressure of 745 torr and a temperature of 26_C, it has a mass of660.59 g.Compound B, a gaseous organic compound that consists of85.6% carbon and 14.4% hydrogen by mass, is placed in a stainlesssteel vessel (10.68 L) with excess oxygen gas. The vessel isplaced in a constant-temperature bath at 22_C. The pressure inthe vessel is 11.98 atm. In the bottom of the vessel is a containerthat is packed with Ascarite and a desiccant. Ascarite is asbestosimpregnated with sodium hydroxide; it quantitatively absorbscarbon dioxide:2NaOH1s2 _ CO21g2!Na2CO31s2 _ H2O1l2