CHEM%245% Spring%2014% Exam%1%Page%1%of%12%%%Part%1%1. What%is%the%correct%electronic%configuration%and%number%of%valence%electrons%for%boron?%%a. 1s22s22p2%/%4%valence%electrons%b. 1s22s12p2%/%5%valence%electrons%c. 1s22s12p2%/%3%valence%electrons%d. 1s22s22p1%/%5%valence%electrons%e. 1s22s22p1%/%3%valen c e%e le c tr o n s %%2. Which%Lewis%structure%is%optimal%f o r%th e %molecule%with%mole cu la r %fo r mula%O2H2%?%%For mal%charges%have%not%been%incl u d e d .%%%%3. Which%statement(s)%is(are)%true%regarding%the%bonding%in%vinyl%fluoride?%%%%%%a. There%are%5%total%sigma%bonds%and %one%pi%bond.%b. The%CNH%bonds%are%formed%by%overlap%of%an%sp2%orbital%on%C%and%a%1S%orbital%on%H.%c. The%CNF%bond%is%formed%by%overlap%of%an%sp2%orbital%on%C%and%an%sp3%orbital%on%F.%d. a%and%b%e. a,%b,%and%c%%4. Order%the%following%according%to%increasing%positive%character%of%the%C%atom,%that%is%the%most%negative%carbon%atom%to%the%most%positive%carbon%atom.%%Most%Negative<Most%positive.%Electronegativity%values:%H=2.1,%C=2.5,%F=4.0,%O=3.5,%Si=1.8,%Li=1.0%%%%a. D<B<C<A<E%b. B<D<E<C<A%c. C<B<D<E<A%d. C<D<B<E<A%e. A<E<B<D<C%%%5. What%is%the%IUPAC%name%of%this%alkane?%%%%a. 3NethylN5Npropylheptane%b. 5NethylN3Npropylheptane%c. transN3,5Ndiethyloctane%d. 3,5Ndiethyloctane%H O O HH O O HH O O H O O HHa.b.c.d.CH3F CH3CH3CH3Li CH3SiH3CH3OHABCD EC CHHHFCH3CH2CHCH2HCCH2CH3CH2CH2CH3CH2CH3CHEM%245% Spring%2014% Exam%1%Page 2 of 12 Points__________ %6. What%is%the%molecular%formula%for%the%skeletal%structure%below?%%%a. C9H12O%b. C9H11O%c. C8H10O%d. C8H9O%e. C7H9O%%%7. Which%letters%in%the%chair%conformation%shown%are%cis %to %t h e %C H3%substitu e n t? %%%a. A%and%B%b. B%and%C%c. C%and%D%d. D%and%E%e. E%and%B%%%%%8. Which%statement(s)%is(are)%true %fo r %th e %most%stable %c o n fo r mation%of%hexane?%%a. Every%CNC%bond%has%an%antiNstaggered%conformation.%b. Torsional%and%steric%strain%are%minimize d .%%c. 1,3%diaxial%interactions%are%minimized.%d. a%and%b%e. a,%b,%and%c%%%9. What%is%the%IUPAC%name%of%this%alkene?%%%%%%%%a. (E)N6NmethylheptN3Nene%b. (Z)N2NmethylheptN4Nene%c. (Z)N6NmethylheptN3Nene%d. (Z)N3NethylN6NmethylheptN4Nene%e. (E)N3NethylN6NmethylheptN3Nene%%HODECH3ABCC CH HCH2CH2CH3CHH3CH3CCHEM%245% Spring%2014% Exam%1%Page 3 of 12 Points__________ %For%questions%10N12,%determine%if%the%alkenes%can%exist%as%stereoisomers.%(2%pts%e ac h ) %% a%=%yes%% b%=%no%% %% %10. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%11. %%%%%%12. %%%%13. Classify%the%reaction%below%as:%%%%a. substitution%%b. elimination%c. addition%d. none%of%the%above%%%%%14. Which%of%the%following%statements%best%describes%the%reaction%with%the%reaction%energy%diagram%below?%%%%%%%%%%%%a. The%reaction%has%3%intermediates%and%the%first%step%is%rate%limiting.%b. The%reaction%has%2%intermediates%and%the%second%step%is%rate%limiting.%c. The%reaction%has%2%intermediates%and%the%first%step%is%rate%limiting.%d. The%reaction%has%3%intermediates%and%the%second%step%is%rate%limiting.%e. The%reaction%has%4%intermediates%and%the%first%step%is%rate%limiting.%%H3CCCH3O+ H2OH3CCCH3HOOHC CCHHH3CH3COC CHClHClC CCH2CH3HHCH2CH3CHEM%245% Spring%2014% Exam%1%Page 4 of 12 Points__________ %For%questions%15N18%indicate%the%relationship%between%each%pair%of%molecules%using%the%choices%below.%%Not%all%letters%must%be%used,%letters%may%be%used%more%than %o n ce .%(2 %pts%eac h)%a. identical%b. constitutional%isomers%c. stereoisomers%%d. conformational%isomers.%%e. Not%related%%15. %%%%%16. %%%%%%%%%%%%%%%%%17. %%%%%%%%%%%%%%18. %%%%%19. Choose%the%statement%or%statements%that%best%explain%why%Markovnikov’s%rule%works.%Markovnivov’s%rule%can%be%used%to%predict%the%major%product%when%HNX%is%added%to%an%alkene%because:%a. When%X%is%bonded%to%a%C%atom%with%a%higher%number%of%C%atoms%bonded%to%it,%the%product%is%more%stable.%b. The%rateNlimiting%step%in%th e%a d dit io n %of%HNX%to%an%alkene%is%carbocation%formation.%%c. The%more%stable%carbocation%has%more%C%atoms%bonded%to%it.%%d. a%and%c%e. b%and%c%%20. Choose%the%best%set%of%words%to%complete%the%following%paragraph.%%%Determining%the%____________________%of%the%alkene%br o mination%re a c tio n %o n %a %c y cl o al k ene,%helped %to%ascertain%the%reaction%mech a n is m.%%The%reaction%product%has%bromine%atoms%________________________%to%one%another%and%therefore%the%reaction%mechanism%has%a%________________________%intermediate.%%%%a. regioselectivit y ,%cis,%ca rb o c a tio n %b. stereoselectivity,%trans,%bromon iu m%ion%c. stereoselectivity,%trans%an d %c is ,%c a rbocation%d. regioselectivity,%trans,%b r o monium %io n%e. stereoselectivity,%cis,%carbocation% %CH3H CH3CH3HH3CCH3H3C HCH3HH3CC CCO2HCH2ClHH3CC CCH2HCO2HClCH3OCHOCHEM%245% Spring%2014% Exam%1%Page 5 of 12 Points__________ %Part%2%%%21. Add%lone%pairs%of%electrons%wherever%they%are%missing%on%the %st ru c tu r e %b e lo w.%(6%pts)%%%%%%%%%%%%22. Add%all%nonNzero%formal%charges%to%the%structure%below:%(4%pts) %%%%%%%23. %a. Draw%the%products.of%the%BronstedNLowry%acid%base%reaction%below.%(4%pts)%pKa%of%ammonium%ion%=%9.24%pKa%of%methoxide%conjugate%acid%=%15.8%%%%%%%%%%%%%%%methoxide%% %%%%%%%%%%%%%%%%%ammonium%%%%%%%%%%%%% %%%%%%%%%%%conjugate%acid%of%methoxide%%%%%%%%%%%%%%%%%%%%%conjugate%base%of%%ammoniu m%%%%%%%b. The%equilibrium%for%this%reaction%lies%on%the%_______________________%side%of%the%reaction.%(2%pts)%%NCCOOHHHHHH3C ONHHH+H+CCCCNHCOFHHHHHCHEM%245% Spring%2014% Exam%1%Page 6 of 12 Points__________ %24. Draw%the%most%stable%and%least%stable%conformations%of%1Nchloropropane,%a b o u t %t h e %C 1 NC2%bond,%on%the%Newman%projection%templates%below,%and%label%them,%most%and%least.%%Inclu d e %al l%atoms%visible%in%the%Newman%projection.%%(5%pts)%%%1Nchloropropane%%%%%% % %%%%%%%_____________ ___ _%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%________________%%%25. %Draw%the%structure%of%1,4NdimethylcyclohexaN1,3Ndiene%(3%pts)%%%26. Assign%high%(H)%and %lo w%(L)%prior itie s %n e x t%t o %th e %groups,%bonded %to%each%C%atom%of%the%doub le%bonds,%and%then%designate%the%E%or%Z%configuration%below%the%structure.%%(6%pts)%%%%%%%%%%%%%%%%%%%%%% %%ClCH2CH2CH3C CNCCH2H3CCCH3ONH2OH3CHC CHCH3CH HCCH3CH3CH2CHEM%245% Spring%2014% Exam%1%Page 7 of 12 Points__________ %27. Draw%the%tw o%chair%conformations%of%neomenthol,%by%comp l e ti n g %t h e %chair%structures%below