Find the total number of statements which are incorrect?

(a) Due to hydrogen bonding HI have higher boiling point than HCL 

(b) If a molecule is planar then it will be non-polar always. 

(c) Among $\mathrm{O}, \mathrm{Si}, \mathrm{Cl}$ and $\mathrm{F}$, fluorine bas highest $\mathrm{I}.{\mathrm{E}}_1$. 

(d) In diamond, fullerene and graphite each carbon has equal covalency. 

(e) Orbitals which are non-directional can only form pie bond.

The correct statements are,

Among $\mathrm{O}, \mathrm{Si}, \mathrm{Cl}$ and $\mathrm{F}$, fluorine bas highest $\mathrm{I}.{\mathrm{E}}_1$. Because it has smaller size than iodine, fluorine has a greater ionization energy than iodine. Therefore, fluorine has a lower shielding effect. Fluorine's nucleus thus draws more valence electrons than iodine's does.

In diamond, fullerene and graphite each carbon has equal covalency. Because In graphite, each carbon atom undergoes ${\mathrm{Sp}}^2$ hybridization and forms 3 bonds with 3 nearby carbon atoms as well as 1 bond. As a result of the discussion above, diamond and graphite are both covalent compounds of carbon (C).