Arrange the following compounds in order of decreasing boiling point,putting the compound with the highest boiling point first.
A)I II III
B)I III II
C)III I II
D)III II I

Question

Arrange the following compounds in order of decreasing boiling point,putting the compound with the highest boiling point first. 
A)I > II > III 
B)I > III > II 
C)III > I > II 
D)III > II > I

Quizplus · Accepted Answer

Compound III is an alcohol, which has strong hydrogen bonding between molecules. This makes it have the highest boiling point. Compound I is an alkane, which has only weak dispersion forces between molecules, and so has the lowest boiling point. Compound II is an ether, which also contains dipole-dipole interactions, but not as strong as hydrogen bonding, and so has a boiling point that falls in between the other two compounds. Therefore, the correct order is III > I > II.

Arrange the Following Compounds in Order of Decreasing Boiling Point,putting