Lewis structure of some typical covalent compounds

The steps in writing Lewis structures of covalent compounds are as follows:

of the molecule by placing the atoms of the combining elements properly. Usually an atom, which forms the largest number of bonds with other atoms is written as the central atom of the structure.

For example in PCl₃ of the following skeleton structures only skeleton structure IV is correct, because Cl atoms cannot form more than one covalent bonds, while P could do.

totally available on each atom in the molecule. Arrange them in such a way that each atom (except hydrogen) is surrounded by eight electrons. Hydrogen atom has only two electrons around it.

The shared electrons are common to both the atoms and are counted as part of the octets around both the atoms.

on the two combining atoms, differently. Dots are put on one atom, and the crosses on the other.

Problem

6. The electronic configuration of a neutral atom 'D' is given as:

1s² 2s² 2p⁵. What is its Lewis structure (empirical formula)?

Solution

The electronic configuration of atom 'D' has seven electrons in the outermost shell. Each 'D' atom should share a pair of electrons with another 'D' atoms to form a substance containing only 'D' .i.e.,

Hence, the formula of the substance is D₂. It is a covalent compound.