Question 1

Which of the following statements best explains why tertiary carbocations are generally more stable than primary carbocations?

Accepted Answer

Tertiary carbocations have more alkyl groups that donate electron density via hyperconjugation and inductive effects.

Question 2

Which reagent would best convert an alkene to a vicinal diol via syn addition?

Accepted Answer

OsO$$_4 ($$osmium tetroxide) followed by NaHSO$$_3$$

Question 3

A student reacts 2-bromopropane with NaOH in ethanol. Which mechanism is most likely to occur and what is the major product?

Accepted Answer

E2 mechanism; propene

Question 4

Which of the following compounds will show a strong, broad absorption around 3300 cm$$^{-1} in $$its IR spectrum?

Accepted Answer

1-butanol

Question 5

Which of the following statements about Markovnikov's rule is correct?

Accepted Answer

In the addition of HX to an alkene, the hydrogen atom adds to the carbon with more hydrogens, and the halide adds to the more substituted carbon.

Question 6

Which of the following is the correct product when benzene reacts with Br$$_2 in $$the presence of FeBr$$_3$$?

Accepted Answer

Bromobenzene

Question 7

A chemist wants to synthesize tert-butyl ether from tert-butyl alcohol and methanol. Which method is most appropriate?

Accepted Answer

React tert-butyl alcohol with methanol in the presence of H$$_2SO$_4 ($$acid catalysis)

Question 8

Which of the following statements about SN2 reactions is correct?

Accepted Answer

SN2 reactions proceed with inversion of configuration at the stereocenter.

Question 9

Which of the following is the major product when 1-butene reacts with HBr in the presence of peroxides?

Accepted Answer

1-bromobutane

Question 10

Which of the following best describes the role of FeCl$$_3 in $$the chlorination of benzene?

Accepted Answer

FeCl$$_3$$ acts as a Lewis acid to generate the electrophilic Cl$$^+$$ species.

Question 11

Which of the following is the correct order of reactivity for the following alkyl halides in an SN1 reaction: tert-butyl bromide, sec-butyl bromide, n-butyl bromide?

Accepted Answer

tert-butyl bromide \u003e sec-butyl bromide \u003e n-butyl bromide

Question 12

Which of the following is a correct statement about the acidity of alcohols and phenols?

Accepted Answer

Phenols are more acidic than alcohols due to resonance stabilization of the phenoxide ion.

Question 13

A student wants to distinguish between 1-butanol and 2-butanone using IR spectroscopy. Which absorption would be present in 2-butanone but absent in 1-butanol?

Accepted Answer

A strong absorption near 1715 cm$$^{-1}$$ due to the C=O stretch

Question 14

Which of the following is the correct product when 1,3-butadiene reacts with HBr at low temperature?

Accepted Answer

1,2-addition product: 3-bromo-1-butene

Question 15

Which of the following statements about the Diels-Alder reaction is correct?

Accepted Answer

The Diels-Alder reaction is a [4+2] cycloaddition between a conjugated diene and a dienophile.

Question 16

Which of the following is the major product when benzene reacts with CH$$_3Cl in $$the presence of AlCl$$_3$$?

Accepted Answer

Toluene

Question 17

Which of the following statements about the reactivity of aromatic compounds in electrophilic aromatic substitution is correct?

Accepted Answer

Electron-donating groups activate the ring and direct substitution to the ortho and para positions.

Question 18

Which of the following is the correct product when 2-methyl-2-butanol is treated with HBr?

Accepted Answer

2-bromo-2-methylbutane

Question 19

Which of the following is the correct order of increasing boiling points for the following compounds: butane, 1-butanol, butanoic acid?

Accepted Answer

Butane \u003c 1-butanol \u003c butanoic acid

Question 20

Which of the following is the correct product when cyclohexene is treated with cold, dilute KMnO$$_4$$?

Accepted Answer

cis-1,2-cyclohexanediol

Organic Chemistry II (CHE251) Final Exam Review Topics: Comprehensive Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard