Observe the following species:
$(i)$ $NH_3$
$(ii)$ $AlCl_3$
$(iii)$ $SnCl_4$
$(iv)$ $CO_2$
$(v)$ $Ag^{+}$
$(vi)$ $HSO_4^{-}$
How many of the above species act as Lewis acids?

What is the formal charge of oxygen atoms in carbon monoxide?

In which of the following molecules,all atoms are coplanar?

Identify the statement$(s)$ which is(are) not correct from the following:
$a)$ $NH_3$ and $H_3O^+$ are isostructural
$b)$ $ClF_3$ has $T$-shape
$c)$ $O_2$ molecule is paramagnetic
$d)$ Bond order of $N_2^+$ is more than $N_2$

The bond length $(pm)$ of $F_2$, $H_2$, $Cl_2$ and $I_2$, respectively is

For the following molecules/ions,identify whether the octet rule is obeyed or not obeyed. Provide the reason.
$(1)$ $PCl_5$ $(2)$ $SF_6$ $(3)$ $PF_5$ $(4)$ $NH_4^+$ $(5)$ $BeCl_2$ $(6)$ $NCl_3$