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Question
Draw the structure of the semicarbazone of ethanal.
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Solution
\[\begin{array}{cc}
\ce{H3C}\phantom{.........................}\ce{O}\phantom{..................}\ce{H}\phantom{..............}\ce{O}\phantom{.............}\\
\phantom{..}\backslash\phantom{........................}||\phantom{...................}|\phantom{...............}||\phantom{...........}\\
\ce{\underset{Ethanal}{C = O} + H2N - NH - C - NH2 -> \underset{Semicarbazone}{CH3 - C = N - NH - C - NH2}}\\
/\phantom{.....................................................................}\\
\ce{H}\phantom{........................................................................}\\
\end{array}\]
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\phantom{....}||\\
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\end{array}\], \[\begin{array}{cc}
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||\\
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