Identify the element having general electronic configuration $ns^2 np^4$ from the following.

How many total statements are correct in the following?
$(i)$ $SO_2$ - antichlor,preservative
$(ii)$ $O_3$ - Disinfectant
$(iii)$ $Cl_2$ - Antiseptic
$(iv)$ $O_2$ - used in oxy-acetylene welding
$(v)$ $PH_3$ - used in smoke screens
$(vi)$ $HNO_3$ - Pickling of stainless steel

Assertion: $Ozone$ is a powerful oxidising agent in comparison to $O_2$.
Reason: $Ozone$ is diamagnetic but $O_2$ is paramagnetic.

Which one of the following is most acidic?

Which of the following oxides of sulfur contains a sulfur-sulfur $(S-S)$ bond?

The acid in which $O-O$ bonding is present is