001version last name first name signatureBIBERDORF CH301unique: 48815, 48830Exam 1Fall 2019Sep 18, 2019Wed 5:30pm - 7pmRemember to refer to the Periodic Table handout that is separate from this exam copy.Version 001 – Exam 1 - F19 – biberdorf – (48815) 2This print-out should have 16 questions.Multiple-choice questions may continue onthe next column or page – find all choicesbefore answering.001 5.0 pointsA sample of methane (CH4) has a compress-ibility factor of 1 at a pressure of 400 atm.Estimate the compressibility factor at a pres-sure of 600 atm.1. 0.62. 1.43. 04. 1002 5.0 points2 moles of A and 2 moles of B are added to aflexible-walled (elastic) container and allowedto react at STP according to the balancedchemical equation:A(g) + 2B(g) → C(g)If the reaction continues until one of the reac-tants runs out, and the initial volume (beforethe reaction sta r ted) was 89.6 L, what is thefinal volume when the reaction is over?1. 112 L2. 22.4 L3. 67.2 L4. 89.6 L5. 44.8 L003 5.0 points17.3 moles of compound A and 25. 8 molesof compound B are mixed at STP and reactaccording to the equation:2A(g) + 3B(g) → 3C(g) + 2D(g)Product C is then isolated at STP from theother components of the mixture. What isthe volume of C?1. 9 65 L2. 2 5.95 L3. 2 5.8 L4. 6 7.2 L5. 5 78 L004 5.0 pointsWhat volume of HF gas is needed to produce1550 L of CF4gas according to the reaction:CCl2F2(g) + HF(g) → CF4(g) + HCl(g)Assume a ll the gases are present at the sametemperature and pressure and CCl2F2is avail-able in excess.1. 7 75 L2. 2 2.4 L3. 1 550 L4. 3 100 L5. 4 4.8 L005 5.0 pointsSelect the following incorrect statement ab outideal gases.1. Gases at the same temperature have thesame average kinetic energy.2. Gases do not attract or repel each other.3. All gas particles have negligible volumewith respect to the size of the container.4. All collisions are inelastic; energy is trans-ferred during collisions.006 5.0 pointsVersion 001 – Exam 1 - F19 – biberdorf – (48815) 3Which of the explanations below best de-scribes the relationship between pressure andvolume for an ideal gas at constant tempera-ture?1. Pressure and volume are directly pro-portional. An increase in the volume of thecontainer results i n an increase in the kineticenergy of the molecules which creates higherpressure.2. Pressure and volume are inversely pro-portional. When you expand the volume ofa container the walls pull the gas moleculesoutward, resulting in a pressure drop in thecenter.3. Pressure and volume are i ndependent o fone another since pressure is measured in at-mospheres and volume is measured in liters.4. Pressure and volume are inversely propor-tional. If the same gas is in a larger container,the mol ecules will hit the walls less frequently,resulting in lower pressure.5. Pressure and volume are directly propor-tional. When you compress a gas, the gasbecomes louder.007 5.0 pointsWhich of the following gases has a mass den-sity of 0.819 g/L at 780 torr and 308 K?1. S22. H23. Kr4. Ne008 5.0 pointsIdentify the unknown gas that has a rate ofeffusion that is 1.07 times faster than oxygengas.1. Ar2. P3. Li24. Cl25. F26. CO009 5.0 pointsAir has a mass density of ab out 1.18 grams perliter at room temperature (25◦C) and 1 atmpressure. What is the mass density of the gasin a helium balloon at the same temperatureand pressure?1. 0 .047 g/L2. 1 .18 g/L3. 1 .95 g/L4. 0 .59 g/L5. 0 .16 g/L010 5.0 pointsAn experiment shows that the velocity of ni-trogen gas ranges from 5 to 1250 m/s at 300 K.In a separate experiment, 1 mole of a n un-known gas is st ored in a 3 L container at300 K. After taking a few measurements, youfind that this gas has a variety of velocitiesranging from 5 to 22 0 0 m/s. What is theidentity of the unknown gas?1. O22. Cl23. He4. SO2011 5.0 pointsWhat is the sum of the coefficients when thischemical equation is balanced using the small-est whole number coefficients?Version 001 – Exam 1 - F19 – biberdorf – (48815) 4FeS2(s) + O2(g) → Fe2O3(s) + SO2(g)1. 252. 143. 214. 65. 10012 5.0 pointsWhat is the pressure of 2.67 × 1023moleculesof iodine gas with a volume of 1.40 L a t285◦C?1. 11.0 atm2. 14.5 atm3. 10.4 atm4. 3.50 atm5. 7.25 atm013 5.0 points6.20 mol of bromobenzene has a pressureof 1.3 0 atm at 450 K. Solve for the vol-ume predicted by the Hard Sphere Modeland the Ideal Gas Law. What is the dif-ference between the predicted volumes if b is0.1539 L/mol for bromobenzene?1. 176 L2. 0.954 L3. 0.200 L4. 0.153 L5. 0.781 L014 5.0 pointsTwo bulbs of gas are connected by a valveand stored at 298 K. The larger bulb containsNe gas with a volume 2.7 L and a pressure of5.43 atm. The smaller bulb contai ns 0.3 molof H2gas. When the valve i s opened, the totalpressure is 5.11 atm. What is the size of thesmall bulb?1. 4 .3 L2. 1 .6 L3. 0 .17 L4. 1 .3 L5. 2 .7 L015 5.0 pointsA container contains 3 atm He and 2 atmH2. What is the mole fracti o n of He in thismixture?1. 0 .52. 0 .63. 1 .54. 0 .45. 0 .3016 5.0 pointsAmmonia is a unique molecule that can cre-ate hydrog en b onds (i.e. has strong attrac-tive forces). Which of the following modelswould you use to calculate the pressure of 0.5moles of ammonia stored in a small container?Why?1. All three models will give approximatelythe same pressure at low volumes.2. Ideal Gas Law ; gases behave ideally atlow volume3. Van der Waals Model; the term nb cor-rects for the att ractive forces and the terman2V2corrects for volume of the particles in theVersion 001 – Exam 1 - F19 – biberdorf – (48815) 5small contai ner4. Hard Sphere Model; the constant b cor-rects for the small container5. Van der Waals Model; the term an2V2cor-rects for the att ractive forces and the termnb corrects for volume of the particles in thesmall contai
View Full Document
Unlocking...