Gidemy

Covalent Bonding

Covalent bonding is the  sharing of electrons between non-metallic atoms for them to gain electronic configuration of an inert gas, to form molecules and compounds.

Convalent bonding is therefore the electrostatic attraction between positively charged protons in the nucleus and the negative shared pair of electrons.

For example

1. hydrogen gas (H₂) is formed by the convalent bonding of two hydrogen atoms.

• Hydrogen atom has one valency. To become stable, it needs one more electron. When 2 hydrogen atoms join, they share their electrons, so that each has two electrons in outemost shell and therby becoming stable or achieving the electron configuration of a noble gas.
  • This type of convalent bonding where one  electron of each atom is shared in a bond is called a single bond repesented as H – H , which means they share one electron pair (2 electrons).

2. Oxygen molecule is formed by convalent bonding of two oxygen atoms.

• An Oxygen atom has 6 valency and needs 2 electrons for it to be stable. Hence, each atom share the amount of electrons each is short of in this case –each share 2 electrons, to form a stable molecule.
  • This type of bonding where each atom share two electrons is called a double bond H = H, which means they share two electron pairs.

3. Water (H₂O) is made up of two atoms of hydrogen and one atom of oxycen.

In water oxygen needs two electrons for it to be stable and hydrogen needs only electron for if to be stable.

Therefore, oxygen shares one electron with two hydrogen atoms to form one molecule of water. Oxygen forms single bonds with the two hydrogen atoms: O – H.

4. Carbon dioxide molecule (CO₂) is made of one atom of carbon and two atoms of Oxygen which are bonded by convalent bonds as shown in the following diagram.

Carbon needs 4 electrons for it to be stable, hence has a valency of 4. Oxygen needs 2 electrons, hence it has a valency of 2 for it to be stable.

For this reason, carbon needs two atoms of oxygen while oxygen needs one atom of Carbon to form a stable molecule.

Carbon and oxygen shares two pairs of electrons form a double bond C = O .

• Convalent bond are generally classified into single bonds, double bonds and tripple bonds. 

• A pair of shared electrons between 2 atoms forms SINGLE BOND, X – Y.  Two pairs of shared electrons between 2 atoms forms DOUBLE BOND, X = Y.

• Three pairs of shared electrons between 2 atoms forms TRIPLE BOND, X ≡ Y.

Uses Of Convalent Compounds

Assigment

1. Describe the uses covalent compounds as nonpolar solvents for covalent compounds
2. Identify the differences in properties of ionic and convalent compounds Differences such as volatility, electrical conductivity, density, melting point, boiling point and basic units.