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Question
What is meant by the following term? Give an example of the reaction in the following case.
2, 4-DNP-derivative
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Solution
When an aldehyde or ketone reacts with 2, 4-dinitrophenylhydrazine in a weak acidic medium, 2, 4-dinitrophenylhydrazone (2, 4-DNP derivative) is produced.

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CH3CHO, \[\begin{array}{cc}
\ce{(CH3)3C-C-CH3}\\
\phantom{....}||\\
\phantom{....}\ce{O}
\end{array}\], \[\begin{array}{cc}
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||\\
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| (i) | ![]() |
| (ii) | ![]() |
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