Question

question 22 (mandatory) (5 points)
rank the following molecules from highest to lowest boiling point temperatures
ethy methyl ether

1. highest

butane

1. 2nd highest

ethanoic acid

1. 3rd highest

but-1-yne

1. 4th highest

propanol

1. lowest

Explanation:

Boiling point is influenced by intermolecular forces. Ethanedioic acid has strong hydrogen bonding and can form dimers (additional intermolecular forces due to double - bonded oxygen and hydroxyl groups). Propanol has hydrogen bonding (from the - OH group). Ethyl methyl ether has dipole - dipole forces (due to the polar C - O bond). But - 1 - yne has weak London dispersion forces (as a non - polar alkyne, but with a linear shape that allows for some better contact compared to butane). Butane has the weakest London dispersion forces among these as it is a non - polar alkane with a more compact shape (compared to but - 1 - yne) leading to less surface contact for London forces.

Answer:

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