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STD 12 -8.1. Aldehydes and ketones — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 12 -8.1. Aldehydes and ketones4 Marks
MCQ
Which is incorrect order for keto-enol stability
  • A

  • ✓
    $\,\begin{array}{*{20}{c}}
      {Ph - C = C{H_2}\, < \,Ph - C - C{H_3}} \\ 
      {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||\,\,\,\,\,} \\ 
      {OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O\,\,\,\,} 
    \end{array}$
  • C
    $\begin{array}{*{20}{c}}
      {C{H_3} - C - C - C{H_3}} \\ 
      {||\,\,\,\,\,\,\,\,\,\,||} \\ 
      {O\,\,\,\,\,\,\,\,\,O} 
    \end{array}$ $\begin{array}{*{20}{c}}
      { > {\mkern 1mu} C{H_2} = C - C - C{H_3}} \\ 
      {\,\,\,\,\,\,\,\,\,\,\,||\,\,\,\,\,\,\,\,||\,\,} \\ 
      {\,\,\,\,\,\,\,\,O\,\,\,\,\,\,\,\,O} 
    \end{array}{\mkern 1mu} $
  • D
    $\begin{array}{*{20}{c}}
      {C{H_3} - C - H} \\ 
      {\,\,\,\,||} \\ 
      {\,\,\,\,O} 
    \end{array}$ $\begin{array}{*{20}{c}}
      { > \,C{H_2} = CH} \\ 
      {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||} \\ 
      {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,OH} 
    \end{array}$
✓

Answer

Correct option: B.
$\,\begin{array}{*{20}{c}}
  {Ph - C = C{H_2}\, < \,Ph - C - C{H_3}} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||\,\,\,\,\,} \\ 
  {OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O\,\,\,\,} 
\end{array}$
b

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