{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Spring 10 Test 1 Key - CHEMISTRY 225 TEST#1 1(27 2(19 NAME...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

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

View Full Document Right Arrow Icon
Background image of page 2
Background image of page 3

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

View Full Document Right Arrow Icon
Background image of page 4
Background image of page 5
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: CHEMISTRY 225 TEST #1 MAY 21, 2010 , . 1. (27) 2. (19) NAME 4 méw w iCc ;z 3. (08) . o o. II " 4' 09 H -C- N. .0: -Cl: ——() e|ectronegativity 2.3 2.5 3.1 3.6 2.9 5_ (12) TOTAL (75) G O O D L U C K ! 1. (27 Points) ORGANIC STRUCTURAL F ORMULAS AND ISOMERISM a. ( / 12) Write condensed structural formulas satisfying each of the following descriptions. Each structure must have at least five carbons. F 0g I ' ‘ ah C‘ C" ' ~ . 3 J 0‘2 0%: (V t '5 cog cu alzur- cu at, C44: CAM/(e an 0 11’ ‘ a secondary amine a branched alkene an aldehyde (,7 at Ufa/Ci“ C 0‘ cu; cu, Qéaé c N 0!; an acid halide a nitriie b. (____ / 4) I (2) Write a condensed structural formula for a compound, Cngg, with a quaternary carbon. 0 (2) Provide the IUPAC name for this compound. 21 2‘A‘1MLflL7iL9Kaua Us; l as; (T. C4 mica} (”908% 2 c. ( / 6) Scientists in Brazil have succeeded in synthesizing the marine natural product spislosine, an anti-tumor agent [Tetrahedron Lett. 2010, 51, 2597]. The structure of spisulosine is shown below as a line formula. m! l NH2 spisulosine l - » r 0 (2) Determine the molecular formula of spisulosine. C: E Hag N O o (2) Directly on the line formula of spisulosine -circle a methylene group. , ~draw an arrow to the most polar bond < 0v 0— N) 0 (2) Convert the line formula of spisulosine to a condensed structural formula. spisulosine, condensed structural formula d. ( / 5) Using any appropriate notation write structures for two isomeric compounds C7H14O with diflerent functional groups 0H C7H14O isomers duct Wdu7 0m 9 . (19 Points) STRUCTURE AND BONDING. a. ( / 4) Acetone, C3H60, is a common organic solvent. It is also the ketone with the fewest carbons. Write a complete structural formula for acetone that shows all bonds and depicts the geometry at each atom clearly. The central carbon atom has been provided for you. You do not have to draw an orbital picture. acetone 3 b. ( / 3) Formamidine is an unusual organic compound with the molecular formula CH4N2. Write a complete structural formula for formamidine showing all bonds and all lone pairs. HINT: The carbon atom is bonded to both nitrogens and a hydrogen. formamidine c. ( / 12) Cysteine, structure below, is an amino acid found in human hair. The German firm Wacher Chemie has developed a new environmentally friendly method for isolating cysteine from natural sources [Chem & Eng. News, April 12, 2010]. 0 (8) Complete the table to the right of the structure of cysteine with the geometry and hybridization at each of the indicated atoms. atom eomet h bridization Ca Ca {’(‘ivéiw Avai 5 O HSCHZCHCOH :L. j ,2 v 1! :‘jg—f NH2\/ C b -O- H 0 pg u aux 5F: cysteine Ci ‘FyvamwlL 7E_ O (2) Which functional group is NOT present in cysteine? (circle one) amino carboxyl sulfhydryi O (2) Complete the equation below to show that cysteine is partially dissociated in aqueous solution. HSCHZCIJHCOgH + H20 H; O + H 4 db 6'1 (/02 NH2 A)”: 3. (08 Points) ORGANIC COMPOUNDS IN THE NEWS. a. ( / 3) Chemists in the United Kingdom /OH have developed a new procedure to effect the I‘ll (I) isomerization reaction to the right [Tetrahedron Lett. 1 M... ’ MNHZ i 2010, 51, 2724]. 2 J o (1) Identify the functional group in the product. a M 1 tit— . (2) Use the functional group approach to predict the product of the reaction below under the same reaction conditions. OH I 9H3 t“ CH3CHCHZCHZCH {/“m” ’0 4 b. ( / 5) According to the May 17 issue of Chemical & Engineering News, esters of valeric acid (valerate esters), derived from lignocellulose, are promising biofuels. The generic structure for a valerate ester is shown below. propyl valerate levulinic acid 0 (3) Write a condensed structural formula for propyl valerate (R = propyl). o (3, BONUS QUESTION!) According to the article in Chemical & Engineering News, hydrolysis of lignocellulose initially produces levulinic acid. Subsequent catalytic hydrogenation of levulinic acid produces valeric acid. Levulinic acid is a derivative of pentanoic acid with a keto group at C(4). Deduce the structure of levulinic acid. 4. (09 Points) THE RESONANCE METHOD. In the presence of a particularly strong acid, acetic acid can serve as a base, that is, a proton acceptor! This property is illustrated below. n H+ CH3COH ——+ a. ( / 4) Provide two additional resonance structures for the protonated form of acetic acid. b. ( / 3) Use the resonance method to compare the carbon-oxygen bond lengths in the protonated form of acetic acid. Which C-O bond is longer? Explain briefly. IV» 1"»!— xlbowauct WKSILOA Wolf (M‘ctv vovi‘LQ'S 0"; I LvC9'l' AYI‘cvtlvetl an, m Vf90w0u¢c Lylwicl/ 7L. wg'ulpl‘cll autvoa!’ 71/1 2 cu wove. «(Gawaucc 947-¢ “We" ”‘4’” m»: a»; ‘va if u'walw‘l 9.4-»: luv”; C94 («Mel C) awal 0M1 v01“ wiv LevJL. Via. Lune C-O LOvJL awe. \cl-zuLacxl Wlw Lourl 0vc‘lrivé Liquw. L0 OL/vcl 2-0 . gofi,» Locale, LQVL m 9%; LCucl ‘ijm 5 c. (2) For which type of compound can the molecular properties best be described by the resonance method? (circle one) _ aldehyde alkene alkane alkyl halide 5. (12 Points) MULTIPLE CHOICE. Write the letter of the correct response in the space to the left of the question. There is only one correct answer for each question. g Identify the molecular orbital to the right. A. 03(Csp3 — H18) B. 0A(Csp3 — H13) c. 1:3(CSp3 ~H13) D. mes}; —Hls) D Determine the IUPAC name of the alkyl halide to the right. CH2CH3 A. 2-ethyl-4-chloroheptane B. 4—chloro-2—ethylheptane CHSCIZHCHZCHCHZCHZCHS C. 4-chloro—7-ethylheptane D. 5-chloro-3—methyloctane Citl C Consider the neutral compound to the right (a nitrile oxide). In which set are the formal charges assigned correctly? A.C=O,N=0,0=0 B. C=0,N=+l,O=—l C.C=+l,N=0,0=-l D.C=-l,N=0,0=+l ’D A certain compound has the molecular formula C7H1202. What combination of 1: bonds might be present in the compound? A. one CEC only B. two C=C C. two C=O D. A, B, and C @ Atomic orbitals on bonded atoms interact to produce a bonding molecular orbital and an antibonding molecular orbital. For which pair of atomic orbitals would the energy level diagram to the right describe the relative energies of the molecular orbitals? D. C2p and Czp C A certain six—carbon hydrocarbon has a set of four collinear carbons. What can one conclude definitively about the compound? A. The hydrocarbon is fully saturated. B. The compound’s molecular formula is C6H12. C. The compound has two sp hybridized carbon atoms. D. The compound is generally unreactive because it lacks any functional groups. ...
View Full Document

{[ snackBarMessage ]}