Question

Arrange these compounds in order of increasing boiling point. (a) 1 -butanol, butane, diethylether (b) hexane, 1 -hexanol, dipropylether

Short answer

Question: Arrange the following compounds in order of increasing boiling point: (a) 1-butanol, butane, diethylether and (b) hexane, 1-hexanol, dipropylether. Answer: (a) Butane < Diethylether < 1-butanol and (b) Hexane < Dipropylether < 1-hexanol.

Step-by-step solution

Identify molecular weights and intermolecular forces

Determine the molecular weights and intermolecular forces present in each compound: 1-butanol: Molecular weight = 74 g/mol; has hydrogen bonding, dipole-dipole, and dispersion forces since it has a hydroxyl group (OH). Butane: Molecular weight = 58 g/mol; has only dispersion forces, as it is a non-polar molecule. Diethylether: Molecular weight = 74 g/mol; has dipole-dipole interactions and dispersion forces due to the oxygen atom, but no hydrogen bonding because there is no OH group.

Order by boiling point

Now that we know the molecular weights and types of intermolecular forces in each compound, we can arrange them in order of increasing boiling point: Butane (lowest boiling point, due to weakest dispersion forces) < Diethylether (dipole-dipole interactions, stronger than dispersion forces but weaker than hydrogen bonding) < 1-butanol (highest boiling point, due to the presence of hydrogen bonding). (b) hexane, 1-hexanol, and dipropylether

Identify molecular weights and intermolecular forces

Determine the molecular weights and intermolecular forces present in each compound: Hexane: Molecular weight = 86 g/mol; has only dispersion forces, as it is a non-polar molecule. 1-hexanol: Molecular weight = 102 g/mol; has hydrogen bonding, dipole-dipole, and dispersion forces since it has a hydroxyl group (OH). Dipropylether: Molecular weight = 114 g/mol; has dipole-dipole interactions and dispersion forces due to the oxygen atom, but no hydrogen bonding because there is no OH group.

Order by boiling point

Now that we know the molecular weights and types of intermolecular forces in each compound, we can arrange them in order of increasing boiling point: Hexane (lowest boiling point, due to weakest dispersion forces) < Dipropylether (dipole-dipole interactions, stronger than dispersion forces but weaker than hydrogen bonding) < 1-hexanol (highest boiling point, due to the presence of hydrogen bonding).