DETERMINATION OF STRUCTURE
(Quiz 9-1)

(A) C=O

(B) C-O

(C) C=C

(D) C-C

2. Which of the following compounds gives an infrared spectrum with peaks at 3000-3500 cm^-1?

(A) 1

(B) 2

(C) 3

(D) 4

3. What is the multiplicity of the signal in the ¹H NMR spectrum for the methyl protons of 2-methylpropane?

(A) singlet

(B) doublet

(C) triplet

(D) nonet

4. Which of the following combinations of peaks appears in the ¹H NMR spectrum of diethyl ether, CH₃CH₂OCH₂CH₃?

(A) a triplet and a doublet

(B) a quartet and a sextet

(C) two singlets

(D) a triplet and a quartet

5. How many signals appear in the proton-decoupled ¹³C NMR spectrum of 1,3-dibromobenzene?

(A) 1

(B) 2

(C) 3

(D) 4

6. How many signals appear in the proton-decoupled ¹³C NMR spectrum of the following compound?

(A) 7

(B) 8

(C) 9

(D) 11

7. The coupling constant, J, between the protons of chloroethane is 7 Hz when the spectrum is obtained at 250 MHz.  What is the coupling constant between these protons when the spectrum is acquired at 500 MHz?

(A) 3.5 Hz

(B) 7 Hz

(C) 14 Hz

(D) 21 Hz

8. What is the hydrogen deficiency index for a compound with a molecular formula of C₆H₆Br₂?

(A) 1

(B) 2

(C) 3

(D) 4

9. Which of the following compounds gives a ¹H NMR spectrum consisting of only a singlet?

(A) 1,1-dibromopropane

(B) 1,2-dibromopropane

(C) 1,3-dibromopropane

(D) 2,2-dibromopropane

10. Which of the following compounds gives a ¹H NMR spectrum consisting of only two triplets and a singlet?

(A) CH₃CH(OCH₃)₂

(B) CH₃OCH₂CH₂CH₂CH₂OCH₃

(C) CH₃OCH₂CH₂OCH₃

(D) CH₃OCH₂CH(OH)CH₃