Arrange the following amines in order of decreasing water solubility,putting the most soluble amine first.
A)I II III
B)II I III
C)III I II
D)II III I

Question

Arrange the following amines in order of decreasing water solubility,putting the most soluble amine first. 
A)I > II > III 
B)II > I > III 
C)III > I > II 
D)II > III > I

Quizplus · Accepted Answer

Amines are basic and can form hydrogen bonds with water through their lone pair of electrons. The water solubility of amines depends on the number of alkyl groups attached to the nitrogen atom. Amines with fewer alkyl groups are more polar and water-soluble, while those with more alkyl groups are less polar and water-insoluble.

In the given amines, II is the most water-soluble amine as it has only one alkyl group (methyl) attached to the nitrogen atom, making it more polar. I has two alkyl groups (ethyl) attached to the nitrogen atom, making it less polar and less water-soluble than II. III has three alkyl groups (propyl) attached to the nitrogen atom, making it even less polar and the least water-soluble among the given amines. Therefore, the correct order of decreasing water solubility is II > I > III, as given in choice B.

Arrange the Following Amines in Order of Decreasing Water Solubility,putting