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प्रश्न
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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उत्तर
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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संबंधित प्रश्न
Acetaldehyde, when treated with which among the following reagents does NOT undergo addition reaction?
(A) Ammonia
(B) Hydroxylamine
(C) Ammoniacal silver nitrate
(D) Semicarbazide
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H2N − NHCONH2/H+
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Predict the product of the following reaction:
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Explain the mechanism of alkaline hydrolysis of tert-butyl bromide with energy profile diagram.
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benzaldehyde from benzoyl chloride
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Write balanced chemical equations for action of ammonia on - acetone
Write balanced chemical equations for action of ammonia on - acetone
Reaction of aqueous sodium hydroxide on chlorobenzene gives which of the following products?
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Acetaldehyde or Propanone
The product "P" in the above reaction is:
The following questions are case-based questions. Read the passage carefully and answer the questions that follow:
| The carbon-oxygen double bond is polarised in aldehydes and ketones due to higher electronegativity of oxygen relative to carbon. Therefore, they undergo nucleophilic addition reactions with a number of nucleophiles such as HCN, NaHSO3, alcohols, ammonia derivatives and Grignard reagents. Aldehydes are easily oxidised by mild oxidising agents as compared to ketones. The carbonyl group of carboxylic acid does not give reactions of aldehydes and ketones. Carboxylic acids are considerably more acidic than alcohols and most of simple phenols. |
Answer the following:
(a) Write the name of the product when an aldehyde reacts with excess alcohol in the presence of dry HCl. (1)
(b) Why carboxylic acid is a stronger acid than phenol? (1)
(c) (i) Arrange the following compounds in increasing order of their reactivity towards CH3MgBr: (1)
CH3CHO, \[\begin{array}{cc}
\ce{(CH3)3C-C-CH3}\\
\phantom{....}||\\
\phantom{....}\ce{O}
\end{array}\], \[\begin{array}{cc}
\ce{CH3-C-CH3}\\
||\\
\ce{O}
\end{array}\]
(ii) Write a chemical test to distinguish between propanal and propanone. (1)
OR
(c) Write the main product in the following: (2)
| (i) |  |
| (ii) |  |
Draw the structure of the following derivative.
The ethylene ketal of hexane-3-one
Draw structure of the following derivative.
The ethylene ketal of hexan-3-one
Draw structures of the following derivatives.
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Draw structures of the given derivatives.
The ethylene ketal of hexan-3-one
