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Question
Write a chemical equation for the following reaction:
Propanone is treated with dilute Ba( OH)2.
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Solution
This is a self-aldol condensation reaction.
\[\begin{array}{cc}
\phantom{............}\ce{CH3} \phantom{........................}\ce{CH3}\phantom{}\\
\phantom{..........................}|\phantom{............................}|\phantom{.................}\\
\ce{\underset{\text{Acetone or propanone}}{2CH3COCH3}<-->[Dil. Ba(OH)2] CH3-C-CH2-CO-CH3->[ ][\Delta]CH3-\underset{\text{4-methyl pent-3-en-2-one}}{C=CH-CO-CH3 }+ H2O}\\
\phantom{..................................}|\phantom{........................} \text{(Aldol condensation product)}\phantom{..}\\
\ce{\underset{\text{4-Hydroxy-4-methyl pentan-2-one(ketol)}}{OH}}\phantom{...................}\\
\end{array}\]
RELATED QUESTIONS
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When liquid ‘A’ is treated with a freshly prepared ammoniacal silver nitrate solution, it gives bright silver mirror. The liquid forms a white crystalline solid on treatment with sodium hydrogensulphite. Liquid ‘B’ also forms a white crystalline solid with sodium hydrogensulphite but it does not give test with ammoniacal silver nitrate. Which of the two liquids is aldehyde? Write the chemical equations of these reactions also.
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When acetaldehyde is treated with dilute NaOH, the following reaction is observed.
\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]
- What are the functional groups in the product?
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