Correct Answer - C
Nitro-compounds reacts with nitrous acid the product depending on the nature of the alkyl group Primary nitro-compounds form nitrolic acids these are crystaline substances which dissolve in sodium hydroxide to give red solution Secondary nitro-compounds form pseudonitroles (pi nitroles) these are colourless crytalline subsatances which dissolve in sodium hydroxide to give blue solutions (the blue color is probably due to the presence of the nitroso -group) Tertiary nitro-compounds do not react with nitrous acid since they have no alpha hydrogen atom Note that these reactions with nitrous acid are the basic of the Victor Meyer test(red white and blue test) for the nature of monohydric alcohols p-hydroxyazobenzene (orange dye)
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