Exam 3B - ‘ kley Fall 2011 Chem.1314 Exam#3 Form B Page 2...

Info icon This preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
Image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ‘ kley, Fall 2011, Chem.1314 Exam #3 Form B. Page 2 of 8. . ‘ Aluminum reacts with excess hydrochloric acid to form aqueous alu ‘ 'num chloride and MB 7 mL of hydrogen gas collected over water at 5&3} and A]; , kPa. If the vapor pressure of water at this temperature is 47. 6 torr how many M. 1K < N grams of aluminum reacted? ‘ “WWW, .- L 6 2.85x10’: Al t We} fiat 717 a 4 H7. 7 Hm B 2.6.4’x10' We 2:84x10'2 D O‘i_8'8x10': L775 E “41:47X10 A ~ 5 652; x 6 awflL -a 5526 ' 7&2) EFT: “RT Obgtg§ :36 37.7 1? £171» /”\ 41?? L ‘ ‘ l; L ,2 1 ~— 1. WW WW ,4. 222w W I lmviwflw 2. Of the following pressure conversions which is incorrect: 1. 0.745 atm = 566 mm Hg 75.5sz ’ 1/ 2. 0.155 kPa = 0.0451 in. Hg 1 mama x 1%“ ~ 3. 36.5 psi = 252 kPa 'M Mm 4. 27 cm Hg = 0.355 atm 7‘ c1 ‘5!- 1‘15 A “A W ..__-, .3 v‘ 5. 3.55 atm = 317 kPa 1557 PM ’9. kart), x (Wm 19%.? 2 ’1 x N \ MI? lal'w L 351W,“ 1.77.7»Wif5 x m”... X A B C , D . @ 31625.3» ! all WWW Z.LG 04”“ X “”73 “1.va \ 3. What is the rms velocity in m/s of uranium (235) hexafluoride at 273.15 °C? (A F“ 15? ‘1 "75141 W u ”.3- 0 l‘ {$.11 kg? h, .‘ 139 0,317qu : B 19.5 ‘1 ‘ #3 C 198 D 262 E None of these is within 10% of the correct answer a: ? 3‘37“! at 2473-77" . g/ t W 7%- 3‘53qu [93 Rockley, Fall 2011, Chem.1314 Exam #3 Form B. Page 3 of 8. 4. How many liters of oxygen at STP are required to react fully with 16 grams of phosphorus to form tetraphosphorus decaoxide at STP? iVfifiXET 79, V\ {1 2 F7 V“). T) A 3.62 v: *5 R) 14.5 (g 57_9 'V‘ fl ”9 +(0; “‘3' now D 1792 “ ‘ P E 80.0 jJ-c VHZT ; .r v Mi;— )‘LJ 3 5. How many photons are emitted by a 17 Watt LED light bulb used for a desk illumination for 9.5 hours of studying chemistry, if the average wavelength of the light is 488 nm (blue light which tends to keep you awake by lowering the rate of production of melatonin, a chemical critical to the circadian rhythm in the human body) it gamma \ n w 5 ® 1.96x10'17 7‘57?“ B 8.40x1022 6: W, C 5.1 (”m D 1.43 x 10 :j 7‘ E 8'84 X ‘0 2;; W t» 23H? m MN" m ~‘ liar": ~~ til i. W 6 Which of the following is not true? A An endothermic reaction absorbs heat as the reaction proceeds @ the enthalpy change for an exothermic reaction is positive C the amount of heat released from an exothermic reaction is proportional to the amount of reactants used up D it the coefficients of an equation are doubled, the amount of enthalpy change per mole of reactions as written also doubles E If more moles of gas are formed than are used in a chemical reaction, the reaction will have a work value that is negative Rockley, Fall 2011, Chem.1314 Exam #3 Form B. Page 4 of 8. 7. What is the wavelength in meters of a photon required to ionize a single electron atom, Li 2+, where the sole electron occupies the n=1 orbit of the Bohr atom? W 2.12» rim '2’ ‘ 1.012 x 10 '8 Q B 1.012x10'8 1.. — C 1.96 x10 17 V D 1.76 x10 —;6 E 9'11X10 1.4013213?) '7..th we”; 8. A 46 9. aluminum engine parts at an initial temperature of 85.9 °C releases 1463 J of heat. lf the specific heat capacity of aluminum is 0.900 J/g-K, what is the final temperature in °C of the part? @ 50.6 116351 9mm x (T? 357.01) B 57.3 m C 54.1 Wu "5’ “ 3‘3’V'QJ‘" 2063326 D 114.5 E 121.2 9. A 0.25 mole sample of sulfur hexafluoride gas at STP is taken to a final pressure of 2.66 atm and 158 °C. What is the final volume in L of the gas? w‘yhfil‘d'gm A 5.60 n/wulj 9” 3 B 1.33 e c 1.218 D 1.40 ' “(if a 3.32 W rt: 0: 0.7.an 312133235"; 1133131 Mmmmum—nw: wx » a 1. W t 'Z.(;C. Rockley, Fall 2011, Chem.1314 Exam #3 Form B. Page 5 of 8. 10. Which of the following combinations of n, l, ml are not allowed? 1. n=1, l= 0, ml=0 2. n=7, I: 1, ml=2 3. n=4, I: 2, ml=—2 4. n=2, I: 2, ml=1 5. n=3 I: 1, ml=—2 1, 2 and 3 2,4 and 5 2,3 and 5 A B C C? 1,3 and 4 only 2 and 5 are not allowed 11. A first iron bolt at 135 °C with twice the mass of the second iron bolt made of identical material is placed in thermal contact with the second iron bolt which is at 45 °C. Both are placed in a calorimeter with negligible heat capacity. What is the final temperature in of the two bolts? A 105 B 75 © 90.0 D 100.0 E This problem cannot be worked unless the specific heat of iron is given 12. Which of the following (of selections A to E) is correct? 1. oxygen diffuses faster than C2H5 at the same temperature 2. sometimes real gases can have a PV/nRT ratio =1 at pressures other than 0.0.atm. 3. intermolecular attractive forces cause the real pressure to be greater than the ideal pressure 4. The ideal gas equation of state is correctly describes the state of real gases only at STP ~5. Ajoule and a liter atm. are both units of energy (sometimes used also as units of work) A 1,2 and 4 are true B 2 and 5 are true C only 2 and 3 are true D all are true (9 2,4 and 5 are true Rockley, Fall 2011, Chem.1314 Exam #3 Form B. Page 6 0f 8. 13. What is the wavelength in meters of a gamma ray emitted by Cobalt — 60, rays used in medical treatment, if the photon has an energy of 1.33 MeV (million electron volts, where 1 electron volt = 1.602 X 10 ‘19 J) 7‘ '3x if“ GD 9.32 x 10 '13 B 2.13 x 10 '13 C between 1.0 and 1000 D 1.24 x 10 ‘6 E There is insufficient information to answer this question (AL 4. 4,2,1; VI???” )1 1.41% 1.15% "'“‘ "'"M‘VW'WM‘mmmw-mnwmnmmnWWW“ u .4 . 1.15 v, 15"”? 14. A 56.8 9. sample of dinitrogen tetroxide is confined in a 4.67 L vessel. What is the pressure in atm. of this gas at 146 °C? W13“; (V: V1947 “m I“? r1172”? A 1.35 v 2. '3" B 5.97 5.3.1... c 2.43 1’ '~ mil 41. @D 3.87 v E 0.109 {44.34 .3... . m.“ >‘ ”W“ 1 ”'1‘? 523 . - , - Wm... We“; L 15. Calculate the molar mass of a gas in g/mol at 435 mm Hg and 62 °C if 456 ng occupies 418 nL. am”; 41va A 283.5 B 997 C 32 1 . - ' D 4.51 x 10 2 , ‘- .. E 52.4 ,. Rockley, Fall 2011, Chem.1314 Exam #3 Form B. Page 7 of 8. 16. A 455 9 piece of copper tubing is heated to 92.5 °C and placed in an insulated vessel containing 140 g of water at 24.5 °C. If the final temperature of the entirety is 38 °C and the heat capacity of the calorimeter containing the water is 8.5 J/K, what is the specific heat capacity of the copper in J/g—K? 3.14 \ Liaby 5.11. x (T510 3.25 1.615 0.972 0.324 moo©> 17. What is the frequency in Hz. of the photon emitted by the electron in a Bohr model of the hydrogen atom in the transition from state n=6 to n = 3. ._ (I ' '2. " (”Rf ; “'1'? \( l 3%: J 3:” [a2 - imam?" 1f». » (337:) MM?“ 18. A chemical reaction releases 417 J of energy and does 96.2 cal of work. What is AE for this reaction in joules? -819 Ag - -321 + 321 — 14.4 A B c D @ —498 « I 2. Witt-21“"? . 2c. 27 /l_ l n a. a 2323x182 3c“ ’71 ’2: "E” - inrhdé “01 = . X " w..- "k ,W «MW. .9 __ 26 ‘ 1...: “1‘7 g ggiilgm ‘ *aflZ'B 8" it... xta ' q"? H ZH’MZ It , 1“ E 12 §.;§..31"i-"ii:.-.- ‘1 .7 _ i“ 7,1334 yW pawn” Rockley, Fall 2011, Chem.1314 Exam #3 Form B. Page 8 of 8. 19. Calculate AH° in kJ per gram of C02 produced by the following reaction: 2C2H6(g) +102(g) “>9C02(9) +loH20(9) A_H°f in kJImol : News?) f7(§43g) s CzHe (g) -84.7 co2 (9) —393.5 H20 (g) -241.8 H20 (I) -285.8 A -2856 B —2586 C 46.2 D - 64.8 0 @ Answer cannot be calculated because you need the enthalpy of formation r oxygen gas or the answer is not within 10% of any of the listed answers 20. Calculate AHO in kJ for 2NOC|(g) 9 Mb) + 02(9) + Cl2(Q) Given the following reactions: 1/2N2(g) + 1[202(9) -> NO(g) AHO = 90.3 kJ ’1 NO(g) + 1/2 Cl2(g) —> NOCl(g) AHO =-38.6 kJ 128.9 61.7 C ~61] ,D E 219.2 403.4 ...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern