JAMB Chemistry 2013 Paper

Concept: Red litmus paper turns blue in a basic (alkaline) solution.Explanation:• A compound that will turn red litmus paper blue must dissolve in water to give an alkaline solution.• Among the given structures, the compound containing an amino group, $\mathrm{-NH_2}$, is an amine.• Amines are weak bases. In aqueous solution, they release $\mathrm{OH^-}$ ions, making the solution alkaline.• Therefore, the amine option is the correct answer.Answer: Option D (the compound with an $\mathrm{-NH_2}$ group)