An organic compound $$'\mathrm{A}'$$ contains nitrogen and chlorine. It dissolves readily in water to give a solution that turns litmus red. Titration of compound $$'\mathrm{A}'$$ with standard base indicates that the molecular weight of $$'\mathrm{A}'$$ is $$131 \pm 2$$. When a sample of $$'\mathrm{A}'$$ is treated with aq. $$\mathrm{NaOH}$$, a liquid separates which contains $$\mathrm{N}$$ but not $$\mathrm{Cl}$$. Treatment of the obtained liquid with nitrous acid followed by phenol gives orange precipitate. The compound $$'\mathrm{A}'$$ is :