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प्रश्न
What is meant by the following term? Give an example of the reaction in the following case.
Acetal
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उत्तर
Gem-dialkoxy compounds in which two alkoxy groups are present on the terminal carbon atom are called acetals. These are formed when the aldehyde reacts with two equivalents of monohydric alcohol in the presence of dry hydrogen chloride.

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संबंधित प्रश्न
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| (i) | ![]() |
| (ii) | ![]() |
| (iii) | ![]() |
| (iv) | ![]() |
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| 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. |
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(c) (i) Arrange the following compounds in increasing order of their reactivity towards CH3MgBr: (1)
CH3CHO, \[\begin{array}{cc}
\ce{(CH3)3C-C-CH3}\\
\phantom{....}||\\
\phantom{....}\ce{O}
\end{array}\], \[\begin{array}{cc}
\ce{CH3-C-CH3}\\
||\\
\ce{O}
\end{array}\]
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OR
(c) Write the main product in the following: (2)
| (i) | ![]() |
| (ii) | ![]() |
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[C] is __________.






