Question

In froth floatation of aniline and cresol aniline acts as

Answer 1

Aniline or Phenylamine is a amine group attached to a phenyl group, or C6H5NH2. The ring structure possesses resonance. Electrons are delocalised from individual atoms and their position varies around the structure. The source of the basicity of the amine group is the lone pair on the nitrogen atom. This lone pair can form a dative covalent bond with a H+ ion. But in Aniline, the lone pair on the nitrogen is also delocalised. It loses the lone pair to resonance, and so cannot donate an electron to a proton, and therefore loses a lot of its basicity. Methylamine, CH3NH2, on the other hand does not possess resonance, and the lone pair on the nitrogen is in place, so it can accept protons, making it basic.