CHEM 2311 HOUR EXAM I NAME 30 SEPTEMBER 2010 100 POINTS TOTAL 1 What is the correct name of the following compound according to IUPAC rules 7 points 2 Dipole moments of alkyl chlorides and alkyl alcohols are strikingly similar yet alcohols boil much higher than the corresponding chlorides Briefly explain the observed difference 5 points 3 Supply the formal charges for the four atoms in the following compound 4 points 1 H C N O 2 4 Indicate which of the following is the stronger acid and briefly explain why To say because as you go the periodic table acidity is not sufficient 6 points a HF and H3COH b H2Se and H2Te c 5 How many sp2 hybridized carbon atoms are present in the following molecule 5 points 3 6 How many 1o primary carbon atoms are present in the molecule in Question 13 above 5 points 4 7 Is propene considered a Lewis Acid or a Lewis Base Explain your logic 5 points 8 Give a proper name for the following compound can choose IUPAC trivial or a combination 8 points 9 Draw a Potential Energy Diagram for an exergonic reaction that is very fast 4 points E R x n C o o r d i n a t e 10 Draw the most stable chair conformer of trans 3 t butyl 1 methylcyclohexane 5 points 5 11 Provide the proper IUPAC name for the following compound 9 points B r 12 Looking down the C3 C4 bond draw the lowest energy conformer using a Newman Projection for the compound shown below 6 points 13 Provide the proper IUPAC name for the following compound and draw the other chair conformer 4 points C l B r 6 7 14 What two atomic orbitals are overlapping to form the bond in ethyne HC 3 points CH a 2sp2 2sp2 b 2sp3 2sp3 c 2sp 2sp d 2p 2p e 2sp 1sp 15 Which statements is are true 3 points a The major reason why the staggered conformer is preferred is due to steric strain b The major reason why the staggered conformer is preferred is due to bonding orbital donation into the orbital c The eclipsed conformer is preferred d The gauche term is used when the two substituents are as far apart as possible 16 In which molecule is the central atom sp3 hybridized 3 points d S o m e o f t h e a b o v e a C H 4 N H 3 H 2 O b c e A l l o f t h e a b o v e f N o n e o f t h e a b o v e 17 Which molecule would you expect to have no dipole moment 3 points a C H F 3 b N F 3 c F H C C d C C e C H 2 F 2 F H F H 18 Which is not an intermolecular force 3 points a Van de Waals d Resonance b Dipole Dipole e Hydrogen bonding c Induced Dipole 19 Which of the following is a true statement 3 points a The stronger the acid the larger its pKa b The conjugate base of a strong acid is a strong base c Acid base reactions always favor the formation of the stronger acid and the stronger base d Strong acids can have negative pKas e Hydrogen need not be present in the molecular formula of a Bronsted Lowry acid H F 8 20 Which of the following are Nucleophiles 3 points a b Z n H 3 C O H H 2 N c d A l l o f t h e a b o v e e N o n e o f t h e a b o v e 9 21 As a 2311 student you were shocked to learn that the most stable conformer of CH2FCH2CH2 looking down the C1 C2 bond was when the F and the CH2 groups were gauche to one another Provide a brief rationale why the gauche conformer was more stable than the other possible conformers 6 points 100 POINTS TOTAL SCORE 10