The correct stability order of the following resonance structures of $CH_3-CH=CH-CHO$ is:

Which of the following compounds will not exist as a resonance hybrid? Give a reason for your answer.
$(a)$ $CH_3OH$
$(b)$ $RCONH_2$
$(c)$ $CH_3CH=CHCH_2NH_2$

Draw the resonance structures of $N_2O_5$,state its shape,and indicate the bond angles and bond lengths.

Despite having an unpaired electron,the $ClO_2$ molecule does not undergo dimerization because .................

Draw the resonance structures for the following compounds. Show the electron shift using curved-arrow notation.
$(a)$ $C_{6}H_{5}OH$
$(b)$ $C_{6}H_{5}NO_{2}$
$(c)$ $CH_{3}CH=CH-CHO$
$(d)$ $C_{6}H_{5}CHO$
$(e)$ $C_{6}H_{5}CH_{2}^{+}$
$(f)$ $CH_{3}CH=CH-CH_{2}^{+}$

Why is benzene extraordinarily stable though it contains three double bonds?