1. Describe the characteristics of a covalent bond.
2. Describe the difference between polar and nonpolar covalent bonds.
molecule molecular substance molecular formula structural formula Lewis structure unshared pair single covalent bond double covalent bond triple covalent bond polar nonpolar
Though we have learned about the forming of bonds through the transfer of electrons, the majority of compounds that we come in contact with in our daily lives are formed in a completely different manner. The atoms are covalently bonded. A covalent bond is one where the electrons are shared. A group of covalently bonded atoms is called a molecule. These molecular substances include DNA, sugar and carbon dioxide. The molecules can contain as few as 2 atoms and as many as a million. Rules for covalent bonds:
Most covalent bonds are slightly polar in nature. What this means is that electrons are not evenly shared between the atoms. This is due to the different electronegativity (electron attracting) values of the individual atoms. Lets look at water (H20):
The resulting molecule is considered polar where oxygen becomes slightly negative and the hydrogen becomes slightly positive.
Molecules can also be non polar. The non polar molecule is electrically neutral and stable. Examples include O2, N2 and F2 You can use the following chart to predict the type of bond.
Last modified: November 08, 2002