Ethanol and dimethyl ether both have the molecular formula
CHEMISTRY · Single correct · CBSE · Chemistry · Chemical Bonding and Molecular Structure · Chemical Bonding and Molecular Structure
Problem
Ethanol and dimethyl ether both have the molecular formula C2H6O. Ethanol has a normal boiling point of 78∘C, whereas dimethyl ether boils at −24∘C. Which of the following best explains this large difference?
(a) Ethanol has a greater molar mass than dimethyl ether, resulting in stronger London dispersion forces.
(b) Dimethyl ether is nonpolar, so only very weak dispersion forces exist between its molecules, whereas ethanol is polar.
(c) Ethanol molecules form extensive hydrogen bonds, whereas dimethyl ether molecules cannot.
(d) Breaking the O−H bond in ethanol requires more energy than separating dimethyl ether molecules, so its boiling point is higher.