Question

Secondary nitroalkanes react with nitrous acid to form

• A. green solution
• B. blue solution
• C. yellow solution
• D. red solution

Hint:

Colour test with nitrous acid: Primary = red, Secondary = blue, Tertiary = no colour.

Answer 1

The Correct Option is B

Step 1: Identify the reaction.
Nitroalkanes react with nitrous acid to give different coloured solutions depending on whether the nitroalkane is primary, secondary, or tertiary.
Step 2: Reaction of secondary nitroalkanes.
Secondary nitroalkanes react with nitrous acid to form pseudonitroles, which produce a blue coloured solution.
Step 3: Compare with other cases.
Primary nitroalkanes give red coloured nitrolic acids, while tertiary nitroalkanes do not give any colour reaction.
Step 4: Conclusion.
Secondary nitroalkanes give a blue coloured solution with nitrous acid.