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Question 1

Classify HOCH₂CH₂OH as protic or aprotic.

Answer 1

A: Protic (it has O-H bonds capable of hydrogen bonding).

Question 2

Classify CH₃CH₂OCH₂CH₃ as protic or aprotic.

Answer 2

A: Aprotic (it lacks O-H or N-H bonds for hydrogen bonding).

Question 3

Classify CH₃COOCH₂CH₃ as protic or aprotic.

Answer 3

A: Aprotic (it has no O-H or N-H bonds).

Question 4

In a polar protic solvent, which is the stronger nucleophile: Br⁻ or Cl⁻?

Answer 4

A: Br⁻ (larger ions are less solvated and more nucleophilic in polar protic solvents).

Question 5

In a polar aprotic solvent, which is the stronger nucleophile: HO⁻ or Cl⁻?

Answer 5

A: HO⁻ (polar aprotic solvents do not solvate anions, so basicity determines nucleophilicity).

Question 6

In a polar protic solvent, which is the stronger nucleophile: HS⁻ or F⁻?

Answer 6

A: HS⁻ (larger anions are less solvated and more nucleophilic in polar protic solvents).

Question 7

Define a polar protic solvent.

Answer 7

A: A solvent with O-H or N-H bonds capable of hydrogen bonding.

Question 8

Define a polar aprotic solvent.

Answer 8

A: A solvent that has no O-H or N-H bonds and cannot form hydrogen bonds.

Question 9

Why are smaller anions more solvated in polar protic solvents?

Answer 9

A: They are more electronegative, leading to stronger hydrogen bonding with the solvent.

Question 10

What determines nucleophilicity in polar aprotic solvents?

Answer 10

A: Basicity, as aprotic solvents do not significantly solvate anions.

Question 11

Why is F⁻ a poor nucleophile in polar protic solvents?

Answer 11

A: F⁻ is highly solvated due to strong hydrogen bonding, reducing its reactivity.

Question 12

Which solvent is likely to dissolve ionic compounds better: polar protic or aprotic?

Answer 12

A: Polar protic solvents, due to hydrogen bonding with ions.

Question 13

What is the effect of hydrogen bonding on nucleophilicity?

Answer 13

A: It decreases nucleophilicity by stabilizing and solvating the nucleophile.

Question 14

Why are Br⁻ and I⁻ strong nucleophiles in polar protic solvents?

Answer 14

A: They are large and less solvated, making them more available for nucleophilic attack.

Question 15

What role does solvation play in determining nucleophilicity?

Answer 15

A: Strong solvation (in polar protic solvents) reduces nucleophilicity, while weak solvation (in polar aprotic solvents) enhances it.