A) acetaldehyde
B) acetone
C) benzaldehyde
D) acetophenone
Correct Answer: A
Solution :
When aliphatic aldehyde is heated with Fehling's solution, to give a red precipitate of cuprous oxide. \[C{{H}_{3}}-\overset{O}{\mathop{\overset{||}{\mathop{C}}\,}}\,-H+\underset{(Fehling\,solution)}{\mathop{2C{{u}^{2+}}+5O{{H}^{-}}}}\,\xrightarrow[{}]{}C{{H}_{3}}-\overset{O}{\mathop{\overset{||}{\mathop{C}}\,}}\,-{{O}^{-}}\]\[+\underset{\begin{smallmatrix} cuprous\,\,oxide \\ (red\,\,precipitate) \end{smallmatrix}}{\mathop{C{{u}_{2}}OO}}\,+3{{H}_{2}}O\] 0 Note: Aromatic aldehyde doesn't give positive Fehling test.You need to login to perform this action.
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