Answer:
Ethanol has the highest boiling point = 78.5°C,
propane has the lowest boiling point = −42.1°C
and the boiling point of dimethyl ether = −23°C
Explanation:
The boiling point of a given substance is the temperature at which a given substance present in the liquid state changes to the vapor state.
The boiling point of the substance depends on the intermolecular forces.
As the strength of the intermolecular forces increases, the boiling point also increases.
The relative strength: Ionic bonds > Hydrogen bonding > dipole-dipole interactions > Van der Waals dispersion forces.
The intermolecular forces present in the following compounds are:
Propane (CH₃CH₂CH₃)- weak van der Waals dispersion forces
Dimethyl ether (CH₃OCH₃)- weak dipole-dipole interactions
Ethanol (CH₃CH₂OH)- strong hydrogen bonding
Therefore, Ethanol has the highest boiling point = 78.5°C, propane has the lowest boiling point = −42.1°C and the boiling point of dimethyl ether = −23°C