Ethylamine is soluble in water whereas aniline is not soluble in water.

Hi Student 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 −C 6H 5 group. Hence, aniline is insoluble in water. H bond is shown here in diagram-->

(i) p K b ​ of aniline is more than that of methylamine. In aniline, the lone pair of electrons on N atom is in resonance with benzene ring. Hence, it cannot be easily donated to an acid. This decreases its basicity. In methyl amine, the + I effect of methyl group increases the electron density on N atom so that the lone pair of electrons on N atom can be easily donated to an acid. Hence, methylamine is more basic than aniline. Higher is the basicity, lower is the p K b and vice versa. (iii) Methylamine in water reacts with ferric chloride to precipitate hydrated ferric oxide. Due to the + I effect of − C H 3 ​ group, methylamine is more basic than water. Therefore, in water, methylamine produces O H − ions by accepting H + ions from water. O H − ions react with ferric chloride to precipitate hydrated ferric oxide.

Account for the following:i p Kb of aniline is more than that of methylamine.ii Ethylamine is soluble in water whereas aniline is not.iii Methylamine in water reacts with ferric chloride to precipitate hydrated ferric oxide.iv Although amino group is o, p directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m nitroaniline.v Aniline does not undergo Friedel Crafts reaction.vi Diazonium salts of aromatic amines are more stable than those of aliphatic amines.vii Gabriel phthalimide synthesis is preferred for synthesising primary amines. Account for the following: (i) p K b of aniline is more than that of methylamine. (ii) Ethylamine is soluble in water whereas aniline is not. (iii) Methylamine in water reacts with ferric chloride to precipitate hydrated ferric oxide. (iv) Although amino group is o, p− directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m-nitroaniline. (v) Aniline does not undergo Friedel-Crafts reaction. (vi) Diazonium salts of aromatic amines are more stable than those of aliphatic amines. (vii) Gabriel phthalimide synthesis is preferred for synthesising primary amines. (i) p K b of aniline is more than that of methylamine: Aniline undergoes resonance and as a result, the electrons on the N-atom are delocalized over the benzene ring. Therefore, the electrons on the N-atom are less available to donate. On the other hand, in case of methylamin...

(i) In aniline, due to resonance, the lone pair of electrons on the nitrogen atom are delocalized over the benzene ring. As a result, the electron density on the nitrogen decreases. On the other hand, in methyl amine +ve I effect of CH 3 increases the electrondensity on the nitrogen atom. Therefore aniline is a weaker base than methyl amine and hence its pK b value is higher than that of methyl amine. (ii) Aniline being a Lewis base reacts with lewis acid AlCl 3 to form a salt. Due to this, N atom of aniline acquires positive charge and hence acts as a strong deactivation group for further reaction. (iii) Ethyl amine is freely soluble in water because it forms hydrogen bonds with water molecules. On the other hand in aniline due to large, hydrocarbon part, the extent of hydrogen bonding decreases considerably and hence aniline is slightly soluble.

Ethylamine is soluble in water whereas aniline is not: Ethylamine when added to water forms intermolecular H−bonds with water. Hence, it is soluble in water. But aniline does not undergo H−bonding with water to a very large extent due to the presence of a large hydrophobic −C 6H 5group. Hence, aniline is insoluble in water.