Question

question 27 (3 points)
rank these compounds in order of increasing boiling point: methoxymethane (ch₃och₃), ethanol (ch₃ch₂oh), and propane (ch₃ch₂ch₃). explain your answer

Explanation:

Boiling point depends on intermolecular forces (IMFs): stronger IMFs → higher boiling point.

• Propane ($\text{CH}_3\text{CH}_2\text{CH}_3$): Nonpolar, only weak London dispersion forces (LDFs).
• Methoxymethane ($\text{CH}_3\text{OCH}_3$): Polar (C-O bonds), so dipole-dipole forces (stronger than LDFs in similar-sized molecules).
• Ethanol ($\text{CH}_3\text{CH}_2\text{OH}$): Has an -OH group, allowing hydrogen bonding (strongest IMF here).

Thus, the order of increasing boiling point is propane < methoxymethane < ethanol.

Answer:

Propane ($\text{CH}_3\text{CH}_2\text{CH}_3$) < methoxymethane ($\text{CH}_3\text{OCH}_3$) < ethanol ($\text{CH}_3\text{CH}_2\text{OH}$)