Draw a Lewis structure for (a) ${\mathbf{SiF}}_4$; (b)${\mathbf{SeCl}}_2$ ; (c)${\mathbf{COF}}_2$(C is central).

A Lewis structure can be defined as the basic structure of a molecule which used the valence electron of each atom involved. In Lewis’s structure, the least electronegative atom will be the central atom.

Si belongs to group 14 having 4 electrons in the valence shell and F belongs to group 17 having 7 electrons in valence and required 1 electron to fulfil its octet.

In the Lewis structure, the Si forms a bond with 4 fluorine atoms by sharing a pair of electrons to fulfil the octet configuration.

${\mathbf{SiF}}_4$ is a Tetrahedral structure

In this molecule, the Se has 6 electrons in the valence orbital and needs 2 electrons to fulfil octet which is given by 2 Cl-atom having 1 electron each.

The Se-atom forms a single bond by sharing one electron with each Cl-atom.

${\mathrm{SeCl}}_2$is a Tetrahedral structure.

The two bond pair electrons and two lone pair of electrons make it a tetrahedral structure.

C belongs to group 14 having 4 electrons in the valence shell requires 4 electrons for octet, O belongs to group 16 having 6 electrons in the valence shell requires 2 electrons for octet and F belongs to group 17 having 7 electrons in the valence shell requires 1 electron to fulfil the octet.

C needs four electrons for octet configuration which is fulfilled by 2 electrons from O-atom and 2 electrons from 2 F-atom.

${\mathrm{COF}}_2$is a Trigonal Planar