The general formula ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}}{\mathrm{O}}_2$ could be for open chain 

The $\mathrm{IUPAC}$ name of the compound shown below is

Write resonating the structure of the below compound.

The correct stability order of the following resonating structures is:

$\left(\mathrm{i}\right) {\mathrm{H}}_2\mathrm{C}=\stackrel{+}{\mathrm{N}}=\stackrel{-}{\mathrm{N}}$

$\left(\mathrm{ii}\right) {\mathrm{H}}_2\stackrel{+}{\mathrm{C}}-\mathrm{N}=\stackrel{-}{\mathrm{N}}$

$\left(\mathrm{iii}\right) {\mathrm{H}}_2\overline{\mathrm{C}}-\stackrel{+}{\mathrm{N}}\equiv \mathrm{N}$

$\left(\mathrm{iv}\right) {\mathrm{H}}_2\overline{\mathrm{C}}-\mathrm{N}=\stackrel{+}{\mathrm{N}}$