⇒ The structure of methylamine is CH₃NH₂

Methylamine is more basic than water due to the presence of CH₃ (electron releasing group) and +I effect (pushing electrons). Being more basic, methylamine accepts a proton from water liberating OH^- ions.

Dissociation of ferric chloride in water to give Fe³⁺ and Cl^-

FeCl₃→ Fe³⁺ + 3Cl^-

Now, the liberated OH^- ions combine with Fe³⁺ ions present in H₂O to form brown precipitate of hydrated ferric oxide.