The number of $\sigma$ and $\pi$ bonds in $O_3$ molecule is:

Find the correct option regarding the given chemical properties.

Identify the correct sequence of increasing number of $\pi$-bonds in the structure of the following molecules:
$(I) \ H_2S_2O_6 \ \ \ \ \ \ \ \ \ (II) \ H_2S_2O_3 \ \ \ \ \ \ \ \ \ (III) \ H_2S_2O_5$

The formal charges of atoms $(1)$,$(2)$ and $(3)$ in the ion $[\underset{(1)}{O}=\underset{(2)}{N}=\underset{(3)}{O}]^{+}$ are:

Which of the following statement$(s)$ is/are correct?

In which of the following compounds is the octet complete $(C)$ or incomplete $(IC)$ for all atoms?
$Al_2Cl_6$ $-$ $Al_2(CH_3)_6$ $-$ $AlF_3$ $-$ Dimer of $BeCl_2$ $-$ Dimer of $BeH_2$
(Note: $C$ for complete octet and $IC$ for incomplete octet.)