Question 1

Which of the following statements best describes the difference between E1 and E2 elimination reactions?

Accepted Answer

E1 reactions occur in two steps with a carbocation intermediate, while E2 reactions occur in a single step without intermediates.

Question 2

In an E1 elimination reaction, which step is typically the rate-determining step?

Accepted Answer

Formation of the carbocation intermediate by loss of the leaving group.

Question 3

Which substrate will react fastest in an E1 elimination reaction?

Accepted Answer

Tertiary alkyl halide ($$R_3CX)$$

Question 4

Which of the following bases is most likely to favor an E2 elimination over an E1 elimination?

Accepted Answer

Potassium tert-butoxide ($$K^+OC(CH_3$)_3^-)$$

Question 5

According to Zaitsev's rule, which product is favored in an E2 elimination reaction?

Accepted Answer

The most substituted alkene.

Question 6

Which of the following energy diagrams best represents an E1 reaction mechanism?

Accepted Answer

Two peaks with an intermediate valley between them.

Question 7

What is the effect of a strong electron-withdrawing group adjacent to a carbonyl group on nucleophilic addition?

Accepted Answer

It increases the reactivity of the carbonyl carbon.

Question 8

Which of the following is true about the nucleophilic addition to aldehydes and ketones?

Accepted Answer

Aldehydes are generally more reactive than ketones due to less steric hindrance and greater electrophilicity.

Question 9

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

Accepted Answer

The hydrogen atom adds to the carbon with the most hydrogens already attached.

Question 10

During the addition of HBr to ethylene, what is the intermediate formed?

Accepted Answer

A carbocation.

Question 11

Which of the following is a requirement for a substrate to undergo a fast E2 elimination?

Accepted Answer

The base and leaving group must be on the same plane.

Question 12

Which of the following is NOT a strong, bulky base commonly used in E2 reactions?

Accepted Answer

Sodium methoxide ($$Na^+$$OCH_3$$^-)$$

Question 13

Which of the following statements about the oxidation of alcohols is correct?

Accepted Answer

Tertiary alcohols are generally resistant to oxidation under normal conditions.

Question 14

What is the major product when 1-methylcyclohexene reacts with HBr in the presence of peroxides?

Accepted Answer

The anti-Markovnikov product.

Question 15

Which of the following best explains why tertiary alkyl halides favor E1 elimination?

Accepted Answer

Tertiary carbocations are the most stable due to hyperconjugation and inductive effects.

Question 16

Which of the following is true about the rate law for an E2 reaction?

Accepted Answer

Rate $$= k 	imes [RX] 	imes [Base]$$

Question 17

Which of the following is a correct statement about the addition of water to alkynes?

Accepted Answer

It requires dilute sulfuric acid and mercuric sulfate as catalysts.

Question 18

Which of the following is the correct product for the oxidation of benzyl alcohol with chromium trioxide ($$CrO_3$$)?

Accepted Answer

Benzaldehyde ($$C_6H_5CHO)$$

Question 19

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

Accepted Answer

A C-H bond is broken and a new C-E bond is formed.

Functional Groups of Organic Compounds and Key Organic Reaction Mechanisms

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