Introduction
Covalent bonding involves sharing of electrons between atoms. The shared electrons bring about an attractive and stable force between the individual forces by forming a full electron shell. Majorly this occurs between non-metal atoms. The electrons can originate from 1 atom or an electron can originate from each 2 atoms. A simple way of indicating the covalent bonds in a molecules is by the use of Lewis structures, or electron dot structures in which the valence electrons of an atom are represented as dots. A stable molecule results whenever a noble gas configuration is achieved for all the atoms-eight (an octet) for the main group atoms or two dots for a hydrogen molecule. The number of covalent bonds in atom forms depends on how many additional valence electrons it needs to reach noble-gas configuration. Valence electrons that are not used for bonding are called lone pair or non-bonding electrons. As a time saving shorthand, nonbonding electrons are often omitted when drawing line bond structure but should be still kept in mind.
The VSEPR theory helps us predict the geometry of molecules based on the electron pairs surrounding the central atom.
Procedure
Molecular structures of various substances were drawn based on the Lewis method. Using the following procedures.
1. The total number of electrons was determined by summating the electrons on each atom.
2. The chemical symbols of the atoms are written in approximation to their neighbors. The least electronegative atom is technically placed at the center.
3. Single covalent bonds are formed using electron pairs linking an atom to its neighbor.
4. Any remaining atoms are placed around the other remaining atoms to complete their octets starting from the terminal atoms. If there aren’t enough electron pairs, one or more pairs are used to form multiple bonds. Any other remaining electrons are placed on the central atom if its P is larger.