CHM-201 General Chemistry and Laboratory I Unit #3 Unit Test November 20, Please pass in this completed answer sheet only.

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1 CHM-201 General Chemistry and Labratry I Unit #3 Unit Test Nvember 20, 2018 Please pass in this cmpleted answer sheet nly.

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3 CHM-201 General Chemistry and Labratry I Unit #3 Unit Test Versin B Nvember 20, 2018 Directins: Cmplete this test and pass in the answer sheet prtin when yu are finished. Please pass in ONLY the answer sheet. On the answer sheet, be sure t enter yur student ID and fill in the apprpriate bubbles. Recrd yur answers unambiguusly ambiguus answers are wrng. D nt crss ut answers either erase/cver them cmpletely r print a new answer sheet (there is crrectin fluid n my desk, if yu need it). Yu may refer t a single 5½ x 8, handwritten index card r equivalent and the peridic table/reference sheet attached t this test. Please leave the classrm when yu are finished. 1. Autmbile air bags inflate during a crash r sudden stp by the rapid generatin f nitrgen gas frm sdium azide. 2NaN 3(s) 2Na(s) 3N 2(g) Hw many mles f sdium azide are needed t prduce sufficient nitrgen t fill a 50.0 L air bag t a pressure f 1.25 atm at 25 C? a ml d ml b ml e ml c ml 2. Using the fllwing data fr water, determine the energy required t melt 1.00 mle f ice (slid water) at its melting pint. Biling pint 373 K Melting pint 273 K Enthalpy f vaprizatin 2,260 J/g Enthalpy f fusin 334 J/g Specific heat capacity (slid) 2.11 J/(g K) Specific heat capacity (liquid) 4.18 J/(g K) Specific heat capacity (gas) 2.08 J/(g K) a kj d kj b kj e kj c kj 3. Assuming that the distances between the tw ins are the same in all cases, which f the fllwing in pairs has the greatest electrstatic ptential energy (i.e., largest in magnitude)? a. d. b. e. c. 4. Which f the fllwing bjects will cl the fastest frm the same initial temperature, assuming yu had equal masses f each? a. an aluminum pan (c s = 0.90 J/(g )) b. a cpper pt (c s = 0.39 J/(g )) c. an irn skillet (c s = 0.45 J/(g )) d. a cntainer f water (4.2 J/(g )) e. a cntainer f ethanl (2.5 J/(g ))

4 5. Hw much wrk des a gas d when it expands against a cnstant pressure f atm frm a vlume f ml t a vlume f ml? (101.3 J = 1 L atm) a J c J b J d J 6. Steam in a cylinder is cmpressed by a pistn exerting a cnstant pressure f 5 atm. The vlume f the cylinder decreases by 15 L and simultaneusly the steam is cled, lsing 105 kj f energy as heat. Hw much energy, ttal, was gained r lst by the steam in this prcess? (101.3 J = 1 L atm) a kj d kj b kj e. 113 kj c. 113 kj 7. Determine the enthalpy fr the fllwing reactin, given (NH 3(g)) = 46.1 kj/ml, (NO(g)) = 90.3 kj/ml, and (H 2O(g)) = kj/ml. 4NH 3(g) 5O 2(g) 4NO(g) 6H 2O(g) H rxn =? kj a kj/ml d kj/ml b. 1,996 kj/ml e kj/ml c. +1,274 kj/ml 8. The integrated circuits in yur cell phne and cmputer are made frm the semicnductr silicn. The silicn is btained frm a really inexpensive starting material, sand, which is primarily SiO 2. One step in the purificatin f silicn is t separate it frm slid impurities by frming the gas silicn tetrachlride. Given the fllwing reactins, what is the verall enthalpy change in cnverting 1.00 ml f silicn dixide int pure silicn? Reactin H (kj) SiO 2(s) 2C(s) Si(impure s) 2CO(g) +690 Si(impure s) 2Cl 2(g) SiCl 4(g) 657 SiCl 4(g) 2Mg(s) 2MgCl 2(s) Si(s) 625 a. +1,972 kj d kj b. 1,972 kj e. 625 kj c. 592 kj 9. Fr which reactin belw des the enthalpy change under standard cnditins crrespnd t a standard enthalpy f frmatin? a. CO(g) H 2O(g) CO 2(g) H 2(g) b. SO 2(g) O 2(g) SO 3(g) c. N 2(g) O 2(g) NO 2(g) d. H 2(g) N 2(g) 3O 2(g) 2HNO 3(g) e. CH 4(g) 2O 2(g) CO 2(g) 2H 2O(g) 10. Hw many mles f prpane are cntained in a 5.00 L tank at 450 trr and 25 C? a ml d. 1,100 ml b. 92 ml e. 41 ml c. 1.4 ml

5 11. A diver jumps ff a diving bard. At which pint in the diagram belw will the diver pssess the greatest ptential energy? a. A d. D b. B e. E c. C 12. Which cntainer shwn belw has the largest partial pressure f helium? The white circles represent helium atms; the dark circles represent argn atms. a. c. b. d. 13. Thermchemistry is the study f hw is prduced and cnsumed during chemical reactins. a. kinetic energy d. wrk b. temperature e. ptential energy c. energy 14. Cnsidering that PV = nrt, which ne f these samples cntains the smallest number f particles? STP = 0 C and 1 atm. a. 2.0 L f H 2 at STP d. 2.0 L f N 2 at 0 C and 900 trr b. 2.0 L f N 2 at STP e. 2.0 L f He at STP c. 2.0 L f H 2 at 25 C and 760 trr

6 15. When 2.50 g f sucrse (mlar mass = g/ml) reacts with excess xygen in a cnstant vlume calrimeter, the temperature f the calrimeter increases by 9.17 C. The heat capacity f the calrimeter is 4.90 kj/ C. Determine the heat f cmbustin per mle f sucrse. a kj/ml d. 6,150 kj/ml b kj/ml e. +6,150 kj/ml c. +1,030 kj/ml 16. What is the temperature f 23.6g f CO 2 gas ccupying 9.01L at a pressure f 3.0 atm? a. 253 C d. 614 C b. 195 C e. 468 C c. 341 C 17. A heating curve fr sme substance is shwn belw. Which f the line segments (I V) represents heating f the slid? a. I d. IV b. II e. V c. III

7 18. The fllwing diagrams illustrate the flw f energy (q) and wrk (w) in different prcesses. Which ne is definitely nt an endthermic prcess? a. d. b. e. c. 19. Dry air cnsists f 78.1% nitrgen (28 g/ml), 20.9% xygen (32 g/ml), 0.9% argn (40 g/ml), 0.03% carbn dixide (44 g/ml), and 0.07% ther gases by vlume. What is the partial pressure f xygen in air when the ttal pressure is 760 trr? a. 594 trr d. 59 trr b. 159 trr e. 236 trr c. 94 trr 20. A sample f gas at 30 C changes vlume frm 20.0 ml t 25.0 ml. If the pressure remained cnstant, what is the final temperature f the gas? a. 31 C d. 106 C b. 31 C e. 74 C c. 24 C 21. Which f the fllwing is unimprtant when using the ideal gas law? a. the chemical identity f the gas sample b. the temperature f the gas sample c. the pressure f the gas sample d. the vlume f the cntainer hlding the gas sample e. the amunt f gas 22. A student disslving sme ammnium nitrate (NH 4NO 3) in water ntices that the beaker gets cler as the slid disslves. This is an example f a. an exthermic prcess. d. a thermdynamic cycle. b. an endthermic prcess. e. all slvatin prcesses. c. a cmbustin reactin.

8 1 H hydrgen 2 He He helium 3 Li Li lithium 4 Be Be beryllium 5 B brn 6 C carbn 7 N nitrgen 8 O xygen 9 F flurine 10 Ne Ne nen 11 Na Na sdium 12 Mg Mg magnesium 13 Al Al aluminum 14 Si Si silicn 15 P phsphrus 16 S sulfur 17 Cl Cl chlrine 18 Ar Ar argn 19 K ptassium 20 Ca Ca calcium 21 Sc Sc scandium 22 Ti Ti titanium 23 V vanadium 24 Cr Cr chrmium 25 Mn Mn manganese 26 Fe Fe irn 27 C C cbalt 28 Ni Ni nickel 29 Cu Cu cpper 30 Zn Zn zinc 31 Ga Ga gallium 32 Ge Ge germanium 33 As As arsenic 34 Se Se selenium 35 Br Br brmine 36 Kr Kr kryptn 37 Rb Rb rubidium 38 Sr Sr strntium 39 Y yttrium 40 Zr Zr zircnium 41 Nb Nb nibium 42 M M mlybdenum 43 Tc Tc (98) technetium 44 Ru Ru ruthenium 45 Rh Rh rhdium 46 Pd Pd palladium 47 Ag Ag silver 48 Cd Cd cadmium 49 In In indium 50 Sn Sn tin 51 Sb Sb antimny 52 Te Te tellurium 53 I idine 54 Xe Xe xenn 55 Cs Cs cesium 56 Ba Ba barium 57 La La lanthanum 72 Hf Hf hafnium 73 Ta Ta tantalum 74 W tungsten 75 Re Re rhenium 76 Os Os smium 77 Ir Ir iridium 78 Pt Pt platinum 79 Au Au gld 80 Hg Hg mercury 81 Tl Tl thallium 82 Pb Pb lead 83 Bi Bi bismuth 84 P P (209) plnium 85 At At (210) astatine 86 Rn Rn (222) radn 87 Fr Fr (223) francium 88 Ra Ra (226) radium 89 Ac Ac (227) actinium 104 Rf Rf (265 rutherfrdium 105 Db Db (268) dubnium 106 Sg Sg (271) seabrgium 107 Bh Bh (273) bhrium 108 Hs Hs (276) hassium 109 Mt Mt (278) meitnerium 110 Ds Ds (281) darmstadtium 111 Rg Rg (283) rentgenium 112 Cn Cn (285) cpernicium 113 Nh Nh (284) nihnium 114 Fl Fl (289) flervium 115 Mc Mc (288) mscvium 116 Lv Lv (293) livermrium 117 Ts Ts (294) tennissine 118 Og Og (294) ganessn THE PERIODIC TABLE OF THE ELEMENTS Bunker Hill Cmmunity Cllege General Chemistry 1 & IA 18 VIIIA 2 IIA 13 IIIA 3 IIIB 15 VA 14 IVA 16 VIA 17 VIIA 4 IVB 5 VB 6 VIB 7 VIIB 11 IB 12 IIB VIIIB B brn Atmic Number Symbl Atmic Mass Name 58 Ce Ce cerium 59 Pr Pr prasedymium 60 Nd Nd nedymium 61 Pm Pm (145) prmethium 62 Sm Sm samarium 63 Eu Eu eurpium 64 Gd Gd gadlinium 65 Tb Tb terbium 66 Dy Dy dysprsium 67 H H hlmium 68 Er Er erbium 69 Tm Tm thulium 70 Yb Yb ytterbium 71 Lu Lu lutetium 90 Th Th thrium 91 Pa Pa prtactinium 92 U uranium 93 Np Np (237) neptunium 94 Pu Pu (244) plutnium 95 Am Am (243) americium 96 Cm Cm (247) curium 97 Bk Bk (247) berkelium 98 Cf Cf (251) califrnium 99 Es Es (252) einsteinium 100 Fm Fm (257) fermium 101 Md Md (258) mendelevium 102 N N (259) nbelium 103 Lr Lr (262) lawrencium Lanthanides Actinides

9 CHEMISTRY INFORMATION SHEET Bunker Hill Cmmunity Cllege General Chemistry 1 & 2 d = m V M = n V m = X A = n m(kg) n A n ttal Frmulas (Density) (Mlarity) (Mlality) (Mle Fractin) M 1 V 1 = M 2 V 2 (Dilutin) M A V A = M B V B (Titratin) P 1 V 1 = P 2 V 2 (Byle s Law) V 1 T 1 = V 2 T 2 P 1 T 1 = P 2 T 2 (Charles s Law) (Gay-Lussac s Law) PV = nrt (Ideal Gas Law) ln P 1 = H vap P 2 R ( 1 T 2 1 T 1 ) (Clausius-Clapeyrn) c = kp (Henry s Law) P 1 = X 1 P 1 (Rault s Law) P = X 2 P 1 (Vapr Pressure Lwering) T b = K b m (Biling Pint Elevatin) T f = K f m (Freezing Pint Depressin) π = MRT (Osmtic Pressure) rate = k[a] x [B] y (Rate Law Expressin) ln k 1 k 2 = E a R ( 1 T 2 1 T 1 ) (Arrhenius Equatin) K = [C]c [D] d [A] a [B] b (Law f Mass Actin) K w = [H + ][OH ] = (In-prduct cnstant) ph = lg[h + ] (ph determinatin) ph = pk a + lg [cnj.base] [acid] (Hendersn-Hasselbalch) G = H T S (Gibb s Free Energy change) E cell = E cathde E ande (Standard Cell emf) 23 atms x10 ml L atm OH J ml K CH 3 COO NO 2 NO 3 2 SO 3 2 SO 4 ClO 4 ClO 3 ClO 2 ClO + NH 4 2 O 2 MnO 4 Hg 2 2+ CN 3 PO 4 2 CO 3 HCO 3 ml K Cnstants (Avgadr s Number) (The Gas Cnstant, R) (The Gas Cnstant, R) Sme Cmmn Plyatmic Ins hydrxide acetate nitrite nitrate sulfite sulfate perchlrate chlrate chlrite hypchlrite ammnium perxide permanganate mercury(i) cyanide phsphate carbnate hydrgen carbnate (bicarbnate) Cnversin Factrs K = atm = 760mmHg(trr) Cnvert Celsius t Kelvin Cnvert t atmspheres