Question

Which of the aldehyde is most reactive?

• A. $C_6{H}_{5}CHO$
• B. $C{H}_{3}CHO$
• C. $HCHO$
• D. All the equally reactive

Answer 1

Answer: (C)

Among carbonyl compounds, reactivity decrease with increase in alkyl groups as alkyl groups ( $+I$ effect) decrease positive character on C-atom. Thus, the correct order of reactivity is-
$HCHO>C{H}_{3}CHO>C_6{H}_{5}CHO$