Question

Why is ethyl amine soluble in water whereas aniline is not?

Answer 1

Ethylamine when added to water forms intermolecular H−bonds with water. And therefore it is soluble in water. But aniline does not form H−bond with water to a very large extent due to the presence of a large hydrophobic −C6H5 group. Hence, aniline is insoluble in water.