Create assignment, 48975, Quiz 2, Feb 13 at 3:18 pm 1This print-out should have 8 questions.Multiple-choice questions may continue onthe next column or page – find all choicesbefore making your selection. The due time isCentral time.PLEASE remember to bubble in yourname, student ID number, and version num-ber on the scantron!Mlib 04 116312:09, basic, multiple choice, > 1 min, fixed.001What volume of hydrogen gas (at STP) wouldbe required to produce 1.00 mole of HCl?H2(g) + Cl2(g) → 2 HCl(g)1. 6.6 L2. 44.8 L3. 22.4 L4. 11.2 L correct5. 5.3 LExplanation:1 mole of an ideal gas at STP (T = 0◦C =273 K, P = 1 atm) has a volume of 22.4 L.If T and P are constant the ideal gas lawreduces toV1V2=n1n2V2=v1n2n11 mol HCl ·1 mol H22 mol HCl= 0.5 mol H2V1= 22.4 Ln1= 1 molV2= ?n2= 0.5 molV2=(22.4 L) (.5 mol)1 mol= 11.2 LMlib 04 113112:14, basic, multiple choice, > 1 min, fixed.002The rate of effusion of gas X is found to beabout 1.3 times that of SF6(g) (MW = 146).The molecular weight of X is about1. 1902. 1103. 86 correct4. 555. 32Explanation:EffX= 1.3 EffSF6MWSF6= 146MWX= XEffXEffSF6=pMWSF6√MWX1.31=√146√MWMWX=Ã√1461.3!2= 86 g/molMsci 12 140212:15, general, multiple choice, > 1 min, fixed.003Which one of the statements below is FALSE?1. A real gas behaves more nearly as an idealgas at high temperatures and low pressures.2. In the van der Waals equation the “a”factor corrects for attractive forces and onewould expect a larger value for “a” for HFthan for He.3. The “b” factor in the van der Waals equa-tion should be larger for He than for Cl2.correct4. Gases approach their liquefaction pointsas temperature decreases and as pressure in-creases.Create assignment, 48975, Quiz 2, Feb 13 at 3:18 pm 25. Both “a” and “b” of the van der Waalsequation have values of zero for an ideal gas.Explanation:Sparks intermol 00313:02, general, multiple choice, < 1 min, fixed.004What type of intermolecular forces wouldyou expect to find in a sample of SO3?1. dipole-dipole2. dispersion correct3. H-bonding4. interionic5. covalentExplanation:SO3has 2 polar S O single bonds, 1 po-lar S O double bond, and no lone pairs onS. The molecule has trigonal planar electronicand molecular geometry. The molecule issymmetric (because the double bond experi-ences resonance) and thus is nonpolar; non-polar molecules experience dispersion forces.Msci 13 0801old13:07, general, multiple choice, > 1 min, fixed.005At 75◦C, the vapor pressures of water,methanol, diethylether, and benzene are 300,1126, 2680, and 644 torr, respectively.0 25 501 atm75 100T (°C)200015001000760500Vapor Pressure (torr)WaterBenzeneMethyl alcoholPlots of the vapor pressures vs tempera-ture of three liquids. The normal boilingpoint of a liquid is the temperature atwhich its vapor pressure is equal to oneatmosphere. Normal boiling points arewater, 100◦C; benzene, 80.1◦C; methylalcohol, 65.0◦C. Notice that the increasein vapor pressure is not linear with tem-perature.Which of these is above the boiling point atatmospheric pressure?1. water only2. diethyl ether only3. all except water4. methanol and diethyl ether correct5. No choice is correct.Explanation:Msci 13 130613:13, general, multiple choice, > 1 min, fixed.006Look at the phase diagram in the handout.Which of the following statements is NOTtrue?1. Water liquid is more dense than ice.2. Carbon dioxide cannot exist as a liquid attemperatures below −57◦C.3. Water cannot exist as a liquid at −5◦C.correct4. Water cannot exist as a liquid at pressuresbelow 4.6 torr.5. We could cause gaseous carbon dioxide tosolidify at −78◦C by increasing the pressureto greater than 1 atm.Explanation:Mlib 05 304515:15, basic, multiple choice, > 1 min, fixed.Create assignment, 48975, Quiz 2, Feb 13 at 3:18 pm 3007For the sublimation of dry iceCO2(s) → CO2(g)1. ∆H > 0, ∆S > 0. correct2. ∆H > 0, ∆S < 0.3. ∆H < 0, ∆S > 0.4. ∆H < 0, ∆S < 0.Explanation:Going from solid to a gas requires ab-sorption of energy (endothermic) because thegaseous molecules have more energy thanmolecules in a solid, so ∆H must be positive.Gaseous compounds are more disordered thansolids, so ∆S would be positive also.Sparks1013:99, general, multiple choice, < 1 min, fixed.008Place the compoundsC2H6, CH4, H2O, HCl, KClin order from lowest to highest boiling point:1. C2H6, CH4, H2O, HCl, KCl2. CH4, C2H6, H2O, HCl, KCl3. CH4, C2H6, HCl, H2O, KCl correct4. KCl, H2O, HCl, C2H6, CH45. CH4, H2O, C2H6, HCl, KCl6. KCl, HCl, C2H6, H2O,
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