Understanding Substitution and Elimination Reactions

Which of the following reactions is impossible with a tertiary substrate?

• SN2

• E2

• SN1

• E1

What is the main reason SN1 and E1 reactions are unlikely with primary substrates?

• Strong nucleophile presence

• High steric hindrance

• Formation of an unstable carbocation

• Formation of a stable carbocation

Which factor makes hydroxide a strong base and good nucleophile?

• Its large size

• Its stability

• Its ability to form hydrogen bonds

• Its instability and reactivity

Why is t-butoxide considered a classic E2 promoter?

• It forms stable carbocations

• It is sterically unhindered

• It is too bulky for SN2

• It is a weak base

How does steric hindrance affect the ability of a base to act as a nucleophile?

• Enhances carbocation formation

• Decreases nucleophilicity

• Has no effect

• Increases nucleophilicity

What happens to leaving group ability as you move down the halogen group?

• It remains the same

• It increases

• It decreases

• It becomes unpredictable

In polar protic solvents, which halide ions are better nucleophiles?

• Smaller halides

• All halides equally

• None of the halides

• Larger halides

What effect does a higher temperature have on elimination reactions?

• Has no effect

• Makes them less spontaneous

• Makes them more spontaneous

• Inhibits them completely

Which reaction type is favored at lower temperatures?

• Elimination

• Substitution

• Both equally

• Neither

What does a positive Delta S indicate in the context of elimination reactions?

• Decrease in entropy

• Increase in entropy

• No change in entropy

• Decrease in enthalpy