Practice Exam 1 - Organic Chemistry | CHEM 2443, Exams of Organic Chemistry

Download Practice Exam 1 - Organic Chemistry | CHEM 2443 and more Exams Organic Chemistry in PDF only on Docsity! PRACTICE EXAM 1 1. (6 pts) Write valid Lewis (electron-dot) structures for each formula below. (note: none of your atoms should have a formal charge) A. BCl2F B. H3CNO 2. Consider the compound below, known as acrylonitrile (8 pts): C C H H H C N A. How many σ-bonds does this molecule contain? _________ B. How many π-bonds does this molecule contain? __________ C. How many unshared electrons does this molecule contain? __________ D. What is the hybridization of the middle carbon of acrylonitrile? __________ 3. For the structure shown below (4 pts): A. What is the hybridization of the carbon atom?________________ B. What is the formal charge on the carbon?________________ C H H : 4. What is the molecular formula of the molecule shown below (3 pts)? ___________________ 2 5. Consider the resonance structures shown below. Rank then in order or increasing contribution to the “true” structure, and briefly justify your answer (5 pts). CH H H C Cl O:: : : : :+ _ CH H H C Cl O:: : : : CH H H C Cl O:: : : : _ + 6. (8 pts) Consider the following eight structures. Circle each molecule that is expected to have a ZERO dipole moment (a non-polar molecule). CF3CBr3 BBr3 NBr3 CCl2=CCl2 CH3OCH3 CH2F2 CF3CF3 CH2O 7. Rank the following substances in order of increasing acidity (8 pts):   NH2OH SH CH3 CH3 O CH3 CH3 O O H H OH CH3 OH O A. B. pKa = 19pKa = 9 pKa = 9.9pKa = 4.76 EXPLAIN YOUR REASONING FOR THE ORDER ON THIS ONE 5 10. (18 pts) Draw a structural formula for each of the following compounds. (a) 6-isopropyl-2,3-dimethylnonane (b) sec-butylcyclopentane (c) 3-tert-butyl-1,1-diethylcycloheptane (c) Draw three alkanes (not alkenes) of structural formula C6H12 6 (3 pts ea. for following questions) 11. Which of the following are constitutional isomers?   A.  I, II, and III B.  I, III, and IV C.  only I and III D.  all are constitutional isomers 12, What are the formal charges of boron and nitrogen, respectively, in the following structure?   A.  -1 and +1 B.  -1 and 0 C.  0 and +1 D.  +1 and -1 13. Arrange the following isomeric alkanes in order of increasing boiling point (1 being the lowest). I. pentane II. 2,2-dimethylpropane III. 2-methylbutane   14. The C—C sigma bond in acetylene is formed by the overlap of which two orbitals?   A.  2p-2p B.  sp-sp C.  sp2-sp2 D.  sp3-sp3  7 1 2 H Radioactive—f54—]+ METALLOID (elementsto left of metalloids He Looe 4 Po |, sremetals: toright, non ‘4008 al. [2 aTomicno? [209)~oppnicar “metals] TSE 77 Je ]s 110 Li |Be ATOMIC WEIGHTS SYMBOL Bic |N |O|F |Ne 6540 | 3.015 10.2 EON 4 OO SIS. S35) 13.00 | 20. 1S3 Parentheses indicate element isartificially a] 12 ‘i rocwced & mass number of longest-lived : 3)Na|Mg| loocope Al|Si|P |S [cl |Ar 2E.5 1 24.32 : E6.9S [25.05 [30.575] 52.06 (FE d57)25-344 13/20 |21 |22 |23 |24 )25 |26 | 27 (28 }29 | so | at Zz s2b434 [25 |36 4E |Ca|lSc {Ti | ¥ [Cr |Mn| Fe | Co| Ni |Cu/2n|Ga|Ge| As | Se | Br | Er E3100) 40.08/44. 56 [47.0 [SoS 52.01 [Sd od [SS SS ES. od | SS. FI 6S.5d [65.55 65.72 | Pe.6O) F431 PS. 36 [Poe | S.20 a7 [ze [39 [40 [41 [42 fas Jaa [45 [ae [47 [49 [49 [50 [sr eseBjss |s4 5)Rb|Sr | ¥ | Zr |Nb/Mo|Tc |Ru/Rh|Pd Ag/Cd |In|Sn|/Sb/Tse|I | xe B5.45 | 87.63 | 35.52 [S22 | 92.5 SS.95 | CS | Oe SI Ob. OSS | EA | SE] 1S. 70 E76 Jer ize 31 15130 55 ]56 |/57 fe (73 | 74 [75 [76 [FF [FB | 7s BO | 31 B2 / 83 sakes [se 6/Cs |Ba|La|Hf |Ta|W |Re|Os|Ir |Pt |Au|Hg|Tl |Pb|Bi |Po] At |Rn 132.51 [137.36 [1.92 178.50/180.95 [183.96 |16.22] 190.2 Lge. [ss.o3] 197.0 200.6104 25) 207 21] 208.5 |rzom) ceo) [eze7 1 ji4 Bis fie fiz fie fe7 fee feo fica fios Pos Halogens Fr |Ra|Ac |R&, |Ha | -- tees eze.o2| e270 |eaenslezezs|czess Noble Gases Alkali 5. Metals 58/59 (60 [61 {62 |63 66 [67 |}68 |69 71 64 [65 70 4) Ce Pr |Nd |Pm|5mJEu |Gd | Tb |Dy|Ho| Er |Tm|¥b |Lu M401 0.52 dd SPIE EOE ISS. S5 JEZ25 USE. SS lez 51 pid sa/ ler 16S. Sd 75.04 7d. 3 oo for fez fos fsa fos foe Far fos feo foo fio ioe fis Th|Pa|U |Np/Pu/Am/Cm/|Bk |Cf | Es |Fm|Md/)|WNo |Lr asz.o4|ce3i jess.or|tasrs|ezdes|(2439|ce45|/(z493| (2513 [ceeds] cess) |ceb|er|ies37|(2609] | Conversion Factors Click Here For "|