$BF_3$ is used as a catalyst in several industrial processes due to its:

Identify a molecule with an incomplete octet from the following.

The number of molecules or ions from the following,which do not have an odd number of electrons are $...............$.
$A. NO_2$ $B. ICl_4^{-}$ $C. BrF_3$ $D. ClO_2$ $E. NO_2^{+}$ $F. NO$

Write the formal charges on atoms in $CO_3^{2-}$ and $HNO_3$.

In the electronic structure of $H_2SO_4$,the total number of unshared electrons is

In which of the following are ionic,covalent,and coordinate bonds present?