Q. An aliphatic nitro compound turns red with the addition of a concentrated $NaOH\$solution, followed by the addition of an excess of an $NaNO_{2}\$solution and then dilute $H_{2}SO_{4}.$ The colour disappears with the addition of the excess of an acid but reappears if the solution is made alkaline. The aliphatic nitro compound is
A) $CH_{3}CH_{2}NO_{2}$
B) $\left( CH_{3} \right)_{2}CHNO_{2}$
C) $\left( CH_{3} \right)_{3}CNO_{2}$
D) All of these
Explanation
(a)
Primary nitro alkanes when treated with nitrous acid from nitrolic acid which when dissolve in alkali gives, salt of nitrolic acid which is red in colour. In excess of acid, the salt dissociated, thus colour disappears while in excess of alkali the red colour reappears
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.