Question

a. Which of the following compounds forms hydrogen bonds between its molecules?

1. CH₃CH₂OCH₂CH₂OH 3. CH₃CH₂CH₂CH₂Br 5. CH₃CH₂CH₂COOH

2. CH₃CH₂N(CH₃)₂ 4. CH₃CH₂CH₂NHCH₃ 6. CH₃CH₂CH₂CH₂F

b. Which of the preceding compounds forms hydrogen bonds with a solvent such as ethanol?

Short answer

1. 1 and 2 forms H bond due to the presence of H in -O-H groups.
2. All the forms do Hydrogen bonding with ethanol.

Step-by-step solution

Definition of Hydrogen bond

Hydrogen is a special type of dipole-dipole attraction between molecules, which is basicallywhen a hydrogen attached to an O, N, or F of one molecule interacts with a lone pair on an O, N, or F of another molecule.

A compound that forms a hydrogen bond must have a hydrogen attached to O, N or F.

Answers regarding H bond in given compounds

Keeping the rules of the above,1 and 5 forms H bonding as they have hydrogen group attached to O-H bond. Ethanol has an H attached to an O, (-O-H) so it can form hydrogen bonds with a compound that has a lone pair on an O, N, or F. Therefore, for this reason, all six compounds’ forms hydrogen bonds with ethanol.