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66E 67E A student titrates an unknown amount of potassiumhydrogen phthalate (KHP) with 20.46 mL of a 0.1000 MNaOH solution. KHP (molar mass =204.22g/mol ) hasone acidic hydrogen. How many grams of KHP weretitrated (reacted completely) by the sodium hydroxidesolution?69E 70E Hydrochloric acid (75.0 mL of 0.250 M) is added to225.0 mL of 0.0550 M Ba(OH)2 solution. What is theconcentration of the excess H+orOH left in thissolution?72E 73E 74E 75E 76E 77E 78E 79E Balance each of the following oxidationreduction reactionsby using the oxidation states method. a. C2H6(g)+O2(g)CO2(g)+H2O(g) b. Mg(s)+HCl(aq)Mg2+(aq)+Cl(aq)+H2(g) c. Cu(s)+Ag+(aq)Cu2+(aq)+Ag(s) d. Zn(s)+H2SO4(aq)ZnSO4(aq)+H2(g)81E 82E 83E 84E 85E 86E 87E 88E 89E 90E 91AE 92AE Consider a 1.50-g mixture of magnesium nitrate andmagnesium chloride. After dissolving this mixture inwater, 0.500 M silver nitrate is added dropwise untilprecipitate formation is complete. This mass of the whiteprecipitate formed is 0.641 g. a. Calculate the mass percent of magnesium chloridein the mixture. b. Determine the minimum volume of silver nitratethat must have been added to ensure complete formationof the precipitate.Suppose 50.0 mL of 0.250 M CoCl2 solution is added to25.0 mL of 0.350 M NiCl2 solution. Calculate the concentration,in moles per liter, of each of the ions presentafter mixing. Assume that the volumes are additive.95AE A mixture contains only NaCland Fe(NO3)3 . A 0.456-gsample of the mixture is dissolved in water, and an excessof NaOH is added, producing a precipitate of Fe(OH)3 . The precipitate is filtered, dried, and weighed.Its mass is 0.107 g. Calculate the following. a. the mass of iron in the sample b. the mass of Fe(NO3)3 in the sample c. the mass percent of Fe(NO3)3 in the sample A mixture contains only sodium chloride and potassiumchloride. A 0.1586-g sample of the mixture was dissolvedin water. It took 22.90 mL of 0.1000 M AgNO3 to completely precipitate all the chloride present. Whatis the composition (by mass percent) of the mixture?98AE A student added 50.0 mL of an NaOH solution to100.0 mL of 0.400 M HCl. The solution was thentreated with an excess of aqueous chromium(III) nitrate,resulting in formation of 2.06 g of precipitate. Determinethe concentration of the NaOH solution.In a 1-L beaker, 203 mL of 0.307 M ammonium chromatewas mixed with 137 mL of 0.269 M chromium(III)nitrite to produce ammonium nitrite and chromium(III)chromate. Write the balanced chemical equation for thereaction occurring here. If the percent yield of the reactionwas 88.0%, how much chromium(III) chromatewas isolated?It took 25.060.05 mL of a sodium hydroxide solutionto titrate a 0.4016-g sample of KHP (see Exercise64). Calculate the concentration and uncertainty in theconcentration of the sodium hydroxide solution. (SeeAppendix Section A1.5.) Neglect any uncertainty in themass.You wish to prepare 1 L of a 0.02 M potassium iodatesolution. You require that the final concentration bewithin 1% of 0.02 M and that the concentration must beknown precisely to the fourth decimal place. How wouldyou prepare this solution? Specify the glassware youwould use, the precision needed for the balance, and theranges of acceptable masses of KIO3 that can be used.Citric acid, which can be obtained from lemon juice, hasthe molecular formula C6H8O7 . A 0.250-g sample ofcitric acid dissolved in 25.0 mL of water requires37.2 mL of 0.105 M NaOH for complete neutralization.How many acidic hydrogens per molecule does citricacid have?Acetylsalicylic acid is the active ingredient in aspirin. Ittook 35.17 mL of 0.5065 M sodium hydroxide to reactcompletely with 3.210 g of acetylsalicylic acid. Acetylsalicylicacid has one acidic hydrogen. What is the molarmass of acetylsalicylic acid?A 6.50-g sample of a diprotic acid requires 137.5 mL ofa 0.750 M NaOH solution for complete neutralization.Determine the molar mass of the acid.106AE Chlorisondamine chloride (C14H20Cl6N2) is a drug usedin the treatment of hypertension. A 1.28-g sample of amedication containing the drug was treated to destroythe organic material and to release all the chlorine aschloride ion. When the filtered solutioncontaining chlorideion was treated with an excess of silver nitrate,0.104 g silver chloride was recovered. Calculate themass percent of chlorisondamine chloride in the medication,assuming the drug is the only source of chloride.Calculate the concentration of all ions present when0.160 g of MgCl2 is dissolved in 100.0 mL of solution.A solution is prepared by dissolving 0.6706 g oxalic acid (H2C2O4) in enough water to make 100.0 mL of solution.A 10.00-mL aliquot (portion) of this solution isthen diluted to a final volume of 250.0 mL. What is thefinal molarity of the oxalic acid solution?For the following chemical reactions, determine the precipitateproduced when the two reactants listed beloware mixed together. Indicate “none” if no precipitate willform.What volume of 0.100 M NaOH is required to precipitateall of the nickel(II) ions from 150.0 mL of a0.249-M solution of Ni(NO3)2 ?112AE A 450.0-mL sample of a 0.257-M solution of silver nitrateis mixed with 400.0 mL of 0.200 M calciumchloride. What is the concentration of Cl in solutionafter the reaction is complete?114AE A 50.00-mL sample of aqueous Ca(OH)2 requires34.66 mL of a 0.944-M nitric acid for neutralization.Calculate the concentration (molarity) of the originalsolution of calcium hydroxide.When organic compounds containing sulfur are burned,sulfur dioxide is produced. The amount of SO2 formedcan be determined by the reaction with hydrogenperoxide: H2O2(aq)+SO2(g)H2SO4(aq) The resulting sulfuric acid is then titrated with a standardNaOH solution. A 1.302-g sample of coal isburned and the SO2 is collected in a solution of hydrogenperoxide. It took 28.44 mL of a 0.1000-M NaOHsolution to titrate the resulting sulfuric acid. Calculatethe mass percent of sulfur in the coal sample. Sulfuricacid has two acidic hydrogens.Assign the oxidation state for the element listed in eachof the following compounds:The blood alcohol (C2H5OH) level can be determined bytitrating a sample of blood plasma with an acidic potassiumdichromate solution, resulting in the production of Cr3+(aq) and carbon dioxide. The reaction can be monitoredbecause the dichromate ion (Cr2O72) is orange insolution, and the Cr3+ ion is green. The unbalanced redoxequation is Cr2O72(aq)+C2H5OH(aq)Cr3+(aq)+CO2(g) If 31.05 mL of 0.0600 M potassium dichromate solutionis required to titrate 30.0 g of blood plasma, determinethe mass percent of alcohol in the blood.Zinc and magnesium metal each react with hydrochloricacid according to the following equations: Zn(s)+2HCl(aq)ZnCl2(aq)+H2(g)Mg(s)+2HCl(aq)MgCl2(aq)+H2(g) A 10.00-g mixture of zinc and magnesium is reactedwith the stoichiometric amount of hydrochloric acid.The reaction mixture is then reacted with 156 mL of3.00 M silver nitrate to produce the maximum possibleamount of silver chloride. a. Determine the percent magnesium by mass in theoriginal mixture. b. If 78.0 mL of HCl was added, what was the concentrationof the HCl?A 10.00-g sample consisting of a mixture of sodiumchloride and potassium sulfate is dissolved in water. Thisaqueous mixture then reacts with excess aqueous lead(II)nitrate to form 21.75 g of solid. Determine the masspercent of sodium chloride in the original mixture.Consider the reaction of 19.0 g of zinc with excess silvernitrite to produce silver metal and zinc nitrite. The reactionis stopped before all the zinc metal has reacted and29.0 g of solid metal is present. Calculate the mass ofeach metal in the 29.0-g mixture.Consider an experiment in which two burets, Y and Z, aresimultaneously draining into a beaker that initially contained275.0 mL of 0.300 M HCl. Buret Y contains0.150 M NaOH and buret Z contains 0.250 M KOH. Thestoichiometric point in the titration is reached 60.65 minutesafter Y and Z were started simultaneously. The totalvolume in the beaker at the stoichiometric point is 655 mL.Calculate the flow rates of burets Y and Z. Assume theflow rates remain constant during the experiment.A sample is a mixture of KCl and KBr. When 0.1024 gof the sample is dissolved in water and reacted with excesssilver nitrate, 0.1889 g of solid is obtained. What isthe composition by mass percent of the mixture?You made 100.0 mL of a lead(II) nitrate solution for labbut forgot to cap it. The next lab session you noticedthat there was only 80.0 mL left (the rest had evaporated).In addition, you forgot the initial concentrationof the solution. You decide to take 2.00 mL of the solutionand add an excess of a concentrated sodium chloridesolution. You obtain a solid with a mass of 3.407 g. What was the concentration of the original lead(II) nitratesolution?Polychlorinated biphenyls (PCBs) have been used extensivelyas dielectric materials in electrical transformers.Because PCBs have been shown to be potentially harmful,analysis for their presence in the environment hasbecome very important. PCBs are manufactured accordingto the following generic reaction: C12H10+nCl2catalystFeC12H10-nCln+nHCl This reaction results in a mixture of PCB products. Themixture is analyzed by decomposing the PCBs and thenprecipitating the resulting Cl as AgCl. a. Develop a general equation that relates the averagevalue of n to the mass of a given mixture of PCBsand the mass of AgCl produced. b. A 0.1947-g sample of a commercial PCB yielded0.4971 g of AgCl. What is the average value of nfor this sample?126CP 127CP Chromium has been investigated as a coating for steelcans. The thickness of the chromium film is determinedby dissolving a sample of a can in acid and oxidizing theresulting Cr3+toCr2O72 with the peroxydisulfate ion: S2O82(aq)+Cr3+(aq)+H2O(l)Cr2O72(aq)+SO42(aq)+H+(aq)(Unbalanced) After removal of unreacted S2O82 , an excess of ferrousammonium sulfate [Fe(NH4)2(SO4)26H2O] is added,reacting with Cr2O72 produced from the first reaction.The unreacted Fe2+ from the excess ferrous ammoniumsulfate is titrated with a separate K2Cr2O7 solution. Thereaction is: H+(aq)+Fe2+(aq)+Cr2O72(aq)Fe3+(aq)+Cr3+(aq)+H2O(l)(Unbalanced) a. Write balanced chemical equations for the tworeactions. b. In one analysis, a 40.0-cm2 sample of a chromiumplatedcan was treated according to this procedure.After dissolution and removal of excess S2O82 ,3.000 g of Fe(NH4)2(SO4)26H2O was added. Ittook 8.58 mL of 0.0520 M K2Cr2O7 solution tocompletely react with the excess Fe2+ . Calculate thethickness of the chromium film on the can. (Thedensity of chromium is 7.19g/cm3 .)129CP Three students were asked to find the identity of themetal in a particular sulfate salt. They dissolved a0.1472-g sample of the salt in water and treated it withexcess barium chloride, resulting in the precipitation ofbarium sulfate. After the precipitate had been filteredand dried, it weighed 0.2327 g. Each student analyzed the data independently andcame to different conclusions. Pat decided that the metalwas titanium. Chris thought it was sodium. Randy reportedthat it was gallium. What formula did each studentassign to the sulfate salt? Look for information on the sulfates of gallium, sodium,and titanium in this text and reference books suchas the CRC Handbook of Chemistry and Physics. Whatfurther tests would you suggest to determine which studentis most likely correct?A sample is a mixture of AgNO3,CuCl2,andFeCl3 .When a 1.0000-g sample of the mixture is dissolved inwater and reacted with excess silver nitrate, 1.7809 g ofprecipitate forms. When a separate 1.0000-g sample ofthe mixture is treated with a reducing agent, all themetal ions in the mixture are reduced to pure metals.The total mass of pure metals produced is 0.4684 g.Calculate the mass percent of AgNO3,CuCl2,andFeCl3 in the original mixture.132MP You have two 500.0-mL aqueous solutions. Solution Ais a solution of a metal nitrate that is 8.246% nitrogenby mass. The ionic compound in solution B consists ofpotassium, chromium, and oxygen; chromium has anoxidation state of +6, and there are 2 potassiums and1 chromium in the formula. The masses of the solutes ineach of the solutions are the same. When the solutionsare added together, a blood-red precipitate forms. Afterthe reaction has gone to completion, you dry the solidand find that it has a mass of 331.8 g. a. Identify the ionic compounds in solution A andsolution B. b. Identify the blood-red precipitate. c. Calculate the concentration (molarity) of all ions inthe original solutions. d. Calculate the concentration (molarity) of all ions inthe final solution.Consider the following apparatus: a test tube coveredwith a nonpermeable elastic membrane inside a containerthat is closed with a cork. A syringe goes throughthe cork. a. As you push down on the syringe, how does themembrane covering the test tube change? b. You stop pushing the syringe but continue to hold itdown. In a few seconds, what happens to themembrane?2DQ 3DQ 4DQ 5DQ 6DQ 7DQ 8DQ 9DQ 10DQ 11DQ 12DQ 13DQ 14DQ 15DQ 16DQ 17DQ For each of the quantities (af) listed below, explainwhich of the following properties (mass of the molecule,density of the gas sample, temperature of the gas sample,size of the molecule, and number of moles of gas) mustbe known to calculate the quantity. a. average kinetic energy b. average number of collisions per second with othergas molecules c. average force of each impact with the wall of thecontainer d. root mean square velocity e. average number of collisions with a given area ofthe container f. distance between collisions 19DQ 20DQ A sealed-tube manometer as shown below can be usedto measure pressures below atmospheric pressure. Thetube above the mercury is evacuated. When there is avacuum in the flask, the mercury levels in both arms ofthe U-tube are equal. If a gaseous sample is introducedinto the flask, the mercury levels are different. The differenceh is a measure of the pressure of the gas insidethe flask. If h is equal to 4.75 cm, calculate the pressurein the flask in torr, pascals, and atmospheres.A diagram for an open-tube manometer is shown below. If the flask is open to the atmosphere, the mercury levelsare equal. For each of the following situations in whicha gas is contained in the flask, calculate the pressure inthe 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.23E 24E A gauge on a compressed gas cylinder reads 2200 psi(pounds per square inch; 1atm=14.7psi ). Express thispressure in each of the following units. a. standard atmospheres b. megapascals (MPa) c. torr 26E 27E 28E 29E 30E A mixture of 1.00 g H2 and 1.00 g He is placed in a1.00-L container at 278C. Calculate the partial pressureof each gas and the total pressure.32E 33E 34E A piece of solid carbon dioxide, with a mass of 22.0 g,is placed in an otherwise empty 4.00-L container at27°C. What is the pressure in the container after all thecarbon dioxide vaporizes? If 22.0 g of solid carbon dioxidewas placed in a similar container already containingair at 740. torr, what would be the partial pressureof carbon dioxide and the total pressure in the containerafter the carbon dioxide had vaporized?36E Suppose two 200.0-L tanks are to be filled separatelywith the gases helium and hydrogen. What mass of eachgas is needed to produce a pressure of 2.70 atm in itsrespective tank at 24°C?38E 39E 40E 41E 42E 43E 44E 45E A sample of nitrogen gas was collected over water at20.°C and a total pressure of 1.00 atm. A total volumeof 2.50102 mL was collected. What mass of nitrogenwas collected? (At 20.°C the vapor pressure of water is17.5 torr.)47E 48E 49E A 1.00-L gas sample at 100.°C and 600. torr contains50.0% helium and 50.0% xenon by mass. What are thepartial pressures of the individual gases?51E 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 temperatureand pressure?53E 54E A compound contains only nitrogen and hydrogen and is87.4% nitrogen by mass. A gaseous sample of the compoundhas a density of 0.977 g/L at 710. torr and 100.°C.What is the molecular formula of the compound?A compound has the empirical formula CHCl. A 256-mL flask, at 373 K and 750. torr, contains 0.800 g of thegaseous compound. Give the molecular formula.One of the chemical controversies of the nineteenth centuryconcerned the element beryllium (Be). Berzeliusoriginally claimed that beryllium was a trivalent element(forming Be3+ ions) and that it formed an oxide with theformula Be2O3 . This assumption resulted in a calculatedatomic mass of 13.5 for beryllium. In formulating hisperiodic table, Mendeleev proposed that beryllium wasdivalent (forming Be2+ ions) and that it gave an oxidewith the formula BeO. This assumption gives an atomicmass of 9.0. In 1894 A. Combes (ComptesRendes, 1894,p. 1221) reacted beryllium with the anion C5H7O2 andmeasured the density of the gaseous product. Combes’sdata for two different experiments are as follows: If beryllium is a divalent metal, the molecular formula of the product will be Be(C5H7O2)2 ; if it is trivalent, theformula will be Be(C5H7O2)3 . Show how Combes’s datahelp to confirm that beryllium is a divalent metal.Discrepancies in the experimental values of the molarmass of nitrogen provided some of the first evidence forthe existence of the noble gases. If pure nitrogen is collectedfrom the decomposition of ammonium nitrite, NH4NO2(s)HeatN2(g)+2H2O(g) its measured molar mass is 28.01. If O2,CO2,andH2O are removed from air, the remaining gas has an averagemolar mass of 28.15. Assuming this discrepancy is solelya result of contamination with argon (atomic mass =39.95 ), calculate the ratio of moles of Ar to moles of N2 in air.A sample of methane (CH4) gas contains a small amountof helium. Calculate the volume percentage of helium ifthe density of the sample is 0.70902 g/L at 0.0°C and1.000 atm.60E 61E Urea (H2NCONH2) is used extensively as a nitrogensource in fertilizers. It is produced commercially fromthe reaction of ammonia and carbon dioxide: 2NH3(g)+CO2(g)pressureHeatH2NCONH2(s)+H2O(g) Ammonia gas at 223°C and 90. atm flows into a reactorat a rate of 500. L/min. Carbon dioxide at 223°C and45 atm flows into the reactor at a rate of 600. L/min.What mass of urea is produced per minute by this reactionassuming 100% yield?Methanol (CH3OH) can be produced by the followingreaction: CO(g)+2H2(g)CH3OH(g) Hydrogen at STP flows into a reactor at a rate of16.0 L/min. Carbon monoxide at STP flows into thereactor at a rate of 25.0 L/min. If 5.30 g of methanol isproduced per minute, what is the percent yield of thereaction?Consider the reaction between 50.0 mL of liquid methanol( CH3OH ; density =0.850g/mL ) and 22.8 L of O2 at27°C and a pressure of 2.00 atm. The products of the reactionare CO2(g)andH2O(g) . Calculate the number ofmoles of H2O formed if the reaction goes to completion.Some very effective rocket fuels are composed of lightweightliquids. The fuel composed of dimethylhydrazine [(CH3)2N2H2] mixed with dinitrogen tetroxide was usedto power the lunar lander in its missions to the moon.The two components react according to the followingequation: (CH3)2N2H2(l)+2N4O4(l)3N2(g)+4H2O(g)+2CO2(g) If 150 g of dimethylhydrazine reacts with excess dinitrogentetroxide and the product gases are collected at 27°Cin an evacuated 250-L tank, what is the partial pressureof nitrogen gas produced and what is the total pressurein the tank assuming the reaction has 100% yield?Air bags are activated when a severe impact causes asteel ball to compress a spring and electrically ignite adetonator cap. This action causes sodium azide (NaN3) to decompose explosively according to the followingreaction: 2NaN3(s)2Na(s)+3N2(g) What mass of NaN3(s) must be reacted to inflate an airbag to 70.0 L at STP?67E 68E 69E Xenon and fluorine will react to form binary compoundswhen a mixture of these two gases is heated to400°C in a nickel reaction vessel. A 100.0-mL nickelcontainer is filled with xenon and fluorine giving partialpressures of 1.24 atm and 10.10 atm, respectively, at atemperature of 25°C. The reaction vessel is heated to400°C to cause a reaction to occur and then cooled to a temperature at which F2 is a gas and the xenon fluorideis a nonvolatile solid. The remaining F2 gas is transferredto another 100.0-mL nickel container where the pressureof F2 at 25°C is 7.62 atm. Assuming all of the xenonhas reacted, what is the formula of the product?The nitrogen content of organic compounds can be determinedby the Dumas method. The compound in questionis first reacted by passage over hot CuO(s): CompoundCuO(s)HotN2(g)+CO2(g)+H2O(g) The gaseous products are then passed through a concentratedsolution of KOH to remove the CO2 . After passagethrough the KOH solution, the gas contains N2 andis saturated with water vapor. In a given experiment, a0.253-g sample of a compound produced 31.8 mL of N2 saturated with water vapor at 25°C and 726 torr. Whatis the mass percent of nitrogen in the compound? (Thevapor pressure of water at 25°C is 23.8 torr.)72E 73E Consider the following balanced equation in which gasX forms gas X2 : 2X(g)X2(g) Equal moles of X are placed in two separate containers.One container is rigid, so the volume cannot change; theother container is flexible, so the volume changes tokeep the internal pressure equal to the external pressure.The above reaction is run in each container. What happensto the pressure and density of the gas inside eachcontainer as reactants are converted to products?75E 76E 77E 78E 79E 80E Calculate the average kinetic energies of the CH4andN2 molecules at 273 K and 546 K.82E 83E 84E 85E 86E 87E One way of separating oxygen isotopes is by gaseousdiffusion of carbon monoxide. The gaseous diffusionprocess behaves like an effusion process. Calculate therelative rates of effusion of 12C16O,12C17O,and12C18O .List some advantages and disadvantages of separatingoxygen isotopes by gaseous diffusion of carbon dioxideinstead of carbon monoxide.A compound contains only C, H, and N. It is 58.51% Cand 7.37% H by mass. Helium effuses through a porousfrit 3.20 times as fast as the compound does. Determinethe empirical and molecular formulas of this compound.90E 91E 92E Why do real gases not always behave ideally? Underwhat conditions does a real gas behave most ideally?Why?94E 95E Without looking at tables of values, which of the followinggases would you expect to have the largest value ofthe van der Waals constant b: H2,N2,CH4,C2H6,orC3H8 ?97E 98E 99E 100E 101E 102E Consider separate 1.0-L samples of O2(g) and He(g),both at 25°C and the same pressure. Compare thechange in momentum per impact and the number ofimpacts per second in the two samples.Consider separate 1.00-L samples of Ar(g), both containingthe same number of moles, one at 27°C and theother at 77°C. Compare the change in momentum perimpact and the number of impacts per second in the twosamples.Calculate the intermolecular collision frequency and themean free path in a sample of helium gas with a volumeof 5.0 L at 27°C and 3.0 atm. Assume that the diameterof a helium atom is 50. pm.106E 107E 108E 109E 110E 111E 112AE 113AE 114AE 115AE 116AE 117AE 118AE A 2.747-g sample of manganese metal is reacted withexcess HCl gas to produce 3.22 L of H2(g) at 373 Kand 0.951 atm and a manganese chloride compound (MnClx) . What is the formula of the manganese chloridecompound produced in the reaction?120AE At STP, 1.0 L Br2 reacts completely with 3.0 L F2 , producing2.0 L of a product. What is the formula of theproduct? (All substances are gases.)122AE 123AE 124AE 125AE 126AE 127AE 128AE 129AE 130AE 131AE 132AE 133AE 134AE 135AE 136AE 137AE 138AE 139AE 140AE 141AE 142AE 143AE 144AE 145AE 146CP A 16.0-g sample of methane (CH4) reacts with 64.0 g ofoxygen gas in a container fitted with a piston (at1.00 atm and 425 K). Methane can react with oxygen toform carbon dioxide and water vapor or carbon monoxideand water vapor. After the combustion reaction iscomplete, the gas density at the given conditions is observedto be 0.7282 g/L. Calculate the mole fraction ofmethane that reacts to form carbon monoxide ratherthan carbon dioxide.You have two samples of helium gas at the same pressurein separate steel containers of the same volume. Youwant the number of collisions of helium atoms with thewalls of container 1 to be twice the number of collisionsof helium atoms with the walls of container 2. Assumeideal behavior. a. How does the temperature in container 1 compareto the temperature in container 2? That is, whichtemperature is larger and by what factor? Explainyour answer and support it mathematically. b. If the number of collisions is different in each container,how can the pressure be the same? Provide awritten explanation with mathematical support.149CP 150CP 151CP 152CP The density of a pure gaseous compound was measuredat 0.00°C as a function of pressure to give the followingresults: Calculate the molar mass of this compound, correctedfor any nonideal behavior of the gas. Assume the nonidealgas obeys the equation PV/nRT=1+P. (Hint:Derive an equation for P/d and plot P/d versus P.)154CP The most probable velocity ump is the velocity possessedby the greatest number of gas particles. At a certain temperature,the probability that a gas particle has the mostprobable velocity is equal to one-half the probabilitythat the same gas particle has the most probable velocityat 300. K. Is the temperature higher or lower than300. K? Calculate the temperature.Derive Dalton’s law of partial pressures from the kineticmolecular theory of gases. What assumptions arenecessary?One of the assumptions of the kinetic molecular theoryis that the volume of a gas particle is negligible. If thiswere the case, the ratio of the number of collisions of gasparticles with the walls of the container compared to thenumber of collisions a given gas particle experienceswith other gas particles should be quite high. Determinethe volume of a cube (in L) filled with helium such thatthe ratio of the number of collisions of helium atomswith the container walls to the number of intermolecularcollisions for a given helium atom is 1 quintillion (1quintillion=1.001018) . The atomic radius of heliumis 3.210-11m .158CP A steel cylinder contains 5.00 moles of graphite (purecarbon) and 5.00 moles of O2 . The mixture is ignitedand all the graphite reacts. Combustion produces a mixtureof CO gas and CO2 gas. After the cylinder hascooled to its original temperature, it is found that thepressure of the cylinder has increased by 17.0%. Calculatethe mole fractions of CO, CO2 , and O2 in the final gaseous mixture.160CP 161CP 162CP Calculate the number of stages needed to change amixture of 13CO2and12CO2 that is originally 0.10%(by moles) 13CO2 to a mixture that is 0.010% 13CO2 by a gaseous diffusion process. (The mass of 13C is13.003355 u.)164CP You have a helium balloon at 1.00 atm and 25°C. Youwant to make a hot-air balloon with the same volumeand same lift as the helium balloon. Assume air is 79.0%nitrogen and 21.0% oxygen by volume. The “lift” of aballoon is given by the difference between the mass ofair displaced by the balloon and the mass of gas insidethe balloon. a. Will the temperature in the hot-air balloon have tobe higher or lower than 25°C? Explain. b. Calculate the temperature of the air required for thehot-air balloon to provide the same lift as thehelium balloon at 1.00 atm and 25°C. Assumeatmospheric conditions are 1.00 atm and 25°C.166CP 167MP 1DQ The boxes shown below represent a set of initial conditionsfor the reaction: Draw a quantitative molecular picture that shows whatthis system looks like after the reactants are mixed inone of the boxes and the system reaches equilibrium.Support your answer with calculations.For the reaction H2(g)+I2(g)2HI(g) , considertwo possibilities using the same-sized, rigid container:(a) you add 0.5 mole of each reactant, allow the systemto come to equilibrium, then add another mole of H2 ,and allow the system to reach equilibrium again, or (b)you add 1.5 moles of H2 and 0.5 mole of I2 and allowthe system to come to equilibrium. Will the final equilibriummixture be different for the two procedures?Explain.Given the reaction A(g)+B(g)C(g)+D(g) , considerthe following situations: i. You have 1.3 M A and 0.8 M B initially. ii. You have 1.3 M A, 0.8 M B, and 0.2 M C initially. iii. You have 2.0 M A and 0.8 M B initially. After equilibrium has been reached, order iiii in termsof increasing equilibrium concentrations of D. Explainyour sequence. Then give the order in terms of increasingequilibrium concentration of B and explain.Consider the reaction A(g)+2B(g)C(g)+D(g) ina 1.0-L rigid flask. Answer the following questions foreach situation (ad): i. Estimate a range (as small as possible) for therequested substance. For example, [A] could bebetween 95 M and 100 M. ii. Explain how you decided on the limits for the estimatedrange. iii. Indicate what other information would enable youto narrow your estimated range. iv. Compare the estimated concentrations for athrough d, and explain any differences. a. If at equilibrium [A]=1M , and then 1 mole of C isadded, estimate the value for [A] once equilibrium isreestablished. b. If at equilibrium [B]=1M , and then 1 mole of C isadded, estimate the value for [B] once equilibrium isreestablished. c. If at equilibrium [C]=1M , and then 1 mole of C isadded, estimate the value for [C] once equilibrium isreestablished. d. If at equilibrium [D]=1M , and then 1 mole of Cis added, estimate the value for [D] once equilibriumis reestablished.Consider the reaction A(g)+B(g)C(g)+D(g) . Afriend asks the following: “I know we have been toldthat if a mixture of A, B, C, and D is at equilibrium andmore of A is added, more C and D will form. But howcan more C and D form if we do not add more B?” Whatdo you tell your friend?Consider the following statements: “Consider the reaction A(g)+B(g)C(g) , at equilibrium in a 1-Lcontainer, with [A]=2M,[B]=1M,and[C]=4M.To this 1-L container you add 3 moles of B. A possiblenew equilibrium condition is [A]=2M,[B]=1M,and[C]=4M because in both cases K=2 .” Indicateeverything you think is correct in these statements andeverything that is incorrect. Correct the incorrect statements,and explain.Le Châtelier’s principle is stated (Section 6.8) as “If agaseous reactant or product is added to a system at equilibrium,the system will shift away from the added component.”The system N2(g)+3H2(g)2NH3(g) isused as an example in which the addition of nitrogen gasat equilibrium results in a decrease in H2 concentrationand an increase in NH3 concentration as equilibrium isreestablished. In this experiment the volume is assumedto be constant. On the other hand, if N2 is added to thereaction system in a container with a piston so that thepressure can be held constant, the concentration of NH3 could actually decrease and the concentration of H2 would increase as equilibrium is reestablished. Explainhow this is possible. Also, if you consider this same systemat equilibrium, the addition of an inert gas, at constantpressure, does affect the equilibrium position. Howis the equilibrium position affected? Explain.The value of the equilibrium constant K depends on whichof the following (there may be more than one answer)? a. the initial concentrations of the reactants b. the initial concentrations of the products c. the temperature of the system d. the nature of the reactants and productsExplain.10E Consider the following reactions at some temperature: 2NOCl(g)2NO(g)+Cl2(g)K=1.61052NO(g)N2(g)+O2(g)K=11031 For each reaction some quantities of the reactants wereplaced in separate containers and allowed to come toequilibrium. Describe the relative amounts of reactantsand products that are present at equilibrium. At equilibrium,which is faster, the forward or reverse reaction ineach case?12E Consider the same reaction as in Exercise 12. In a particularexperiment 1.0 mole of H2O(g) and 1.0 mole ofCO(g) are put into a flask and heated to 350°C. In anotherexperiment 1.0 mole of H2(g) and 1.0 mole of CO2(g) are put into a different flask with the same volumeas the first. This mixture is also heated to 350°C.After equilibrium is reached, will there be any differencein the composition of the mixtures in the two flasks?Consider the following reaction at some temperature: H2O(g)+CO(g)H2(g)+CO2(g)K=2.0 Some molecules of H2O and CO are placed in a 1.0-Lcontainer as shown below. When equilibrium is reached, how many molecules of H2O,CO,H2,andCO2 are present? Do this problem bytrial and error—that is, if two molecules of CO react, isthis equilibrium; if three molecules of CO react, is thisequilibrium; and so on.15E 16E 17E 18E Explain the difference between K, Kp , and Q.20E 21E For which reactions in Exercise 21 is Kp equal to K?23E 24E At 327°C, the equilibrium concentrations are [CH3OH]=0.15M,[CO]=0.24M,and[H2]=1.1M for the reaction CH3OH(g)CO(g)+2H2(g) Calculate Kp at this temperature.26E At a particular temperature, a 2.00-L flask at equilibriumcontains 2.8010-4moleofN2,2.5010-5moleofO2,and2.0010-2moleofN2O . Calculate K at thistemperature for the reaction 2N2(g)+O2(g)2N2O(g) If [N2] 5 2.00 3 1024 M, [N2O] 5 0.200 M, and [O2] 50.00245 M, does this represent a system at equilibrium?28E 29E 30E 31E Nitrogen gas (N2) reacts with hydrogen gas (H2) to formammonia (NH3) . At 200°C in a closed container, 1.00 atmof nitrogen gas is mixed with 2.00 atm of hydrogen gas.At equilibrium, the total pressure is 2.00 atm. Calculatethe partial pressure of hydrogen gas at equilibrium, andcalculate the value of Kp for this reaction.A sample of gaseous PCl5 was introduced into an evacuatedflask so that the pressure of pure PCl5 would be0.50 atm at 523 K. However, PCl5 decomposes to gaseous PCl3 and Cl2 , and the actual pressure in the flaskwas found to be 0.84 atm. Calculate Kp for the decompositionreaction PCl5(g)PCl3(g)+Cl2(g) at 523 K. Also calculate K at this temperature.34E 35E At a particular temperature, 8.0 moles of NO2 is placedinto a 1.0-L container and the NO2 dissociates by thereaction 2NO3(g)2NO2(g)+O2(g) At equilibrium the concentration of NO(g) is 2.0 M.Calculate K for this reaction.37E 38E 39E 40E At a particular temperature, K=1.00102 for thereaction H2(g)+I2(g)2HI(g) In an experiment, 1.00 mole of H2 , 1.00 mole of I2 , and1.00 mole of HI are introduced into a 1.00-L container.Calculate the concentrations of all species when equilibriumis reached.42E 43E For the reaction below at a certain temperature, it isfound that the equilibrium concentrations in a 5.00-Lrigid container are [H2]=0.0500M,[F2]=0.0100M,and[HF]=0.400M . H2(g)+F2(g)2HF(g) If 0.200 mole of F2 is added to this equilibrium mixture,calculate the concentrations of all gases once equilibriumis reestablished.At 1100 K, Kp=0.25 for the following reaction: 2SO2(g)+O2(g)2SO3(g) Calculate the equilibrium partial pressures of SO2,O2,andSO3 produced from an initial mixture in which PSO2=PO2=0.50atmandPSO3=0 .At 2200°C, K=0.050 for the reaction N2(g)+O2(g)2NO(g) What is the partial pressure of NO at equilibrium assumingthe N2andO2 had initial pressures of 0.80 atmand 0.20 atm, respectively?47E 48E 49E 50E 51E 52E 53E 54E Which of the following statements is(are) true? Correct the false statement(s). a. When a reactant is added to a system at equilibriumat a given temperature, the reaction will shift rightto reestablish equilibrium. b. When a product is added to a system at equilibriumat a given temperature, the value of K for the reactionwill increase when equilibrium is reestablished. c. When temperature is increased for a reaction atequilibrium, the value of K for the reaction willincrease. d. Addition of a catalyst (a substance that increases thespeed of the reaction) has no effect on the equilibriumposition.56E 57E 58E Chromium(VI) forms two different oxyanions, the orangedichromate ion (Cr2O72) , and the yellow chromate ion (CrO42) . (See the photos below.) The equilibriumreaction between the two ions is Cr2O72(aq)+H2O(l)2CrO42(aq)+2H+(aq) Explain why orange dichromate solutions turn yellowwhen sodium hydroxide is added.Solid NH4HS decomposes by the following endothermicprocess: NH4HS(s)NH3(g)+H2S(g) a. What effect will adding more NH3(g) have on theequilibrium? b. What effect will adding more NH4HS(s) have on theequilibrium? c. What effect will increasing the volume of the containerhave on the equilibrium? d. What effect will decreasing the temperature have onthe equilibrium?An important reaction in the commercial production ofhydrogen is CO(g)+H2O(g)H2(g)+CO2(g) How will this system at equilibrium shift in each of thefive following cases? a. Gaseous carbon dioxide is removed. b. Water vapor is added. c. In a rigid reaction container, the pressure isincreased by adding helium gas. d. The temperature is increased (the reaction isexothermic). e. The pressure is increased by decreasing the volumeof the reaction container.62E 63E 64E 65E

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