Question

question 22 (mandatory) (5 points)
rank the following molecules from highest to lowest boiling point temperatures
but-1-yne

1. highest

propanol

1. 2nd highest

ethy methyl ether

1. 3rd highest

ethanoic acid

1. 4th highest

butane

1. lowest

Explanation:

• Ethanolic acid: It has strong hydrogen - bonding and also forms dimers through hydrogen - bonding. The intermolecular forces are very strong, so it has a high boiling point.
• Propanol: It has hydrogen - bonding due to the - OH group. Hydrogen - bonding is a relatively strong intermolecular force.
• But - 1 - yne: It has dipole - dipole interactions (because of the polar C - C triple bond) and London dispersion forces.
• Ethyl methyl ether: It has dipole - dipole interactions (due to the polar C - O - C bond) and London dispersion forces. But the dipole - dipole forces in ether are weaker compared to the hydrogen - bonding in alcohols and acids.
• Butane: It only has London dispersion forces, which are the weakest among the intermolecular forces considered here.

Answer:

1. Ethanolic acid
2. Propanol
3. But - 1 - yne
4. Ethyl methyl ether
5. Butane