Chemical Bonds Made Simple - Ionic, Covalent, and Polar Covalent Bonds

There are three main types of chemical bonds, and this article will give an easy outline for chemistry students. The three chemical bonds that will be covered are ionic bonding, covalent bonding and polar covalent bonding.

Chemical bonds can be described as a force that holds together groups of two or more atoms so that the atoms function as one unit. Luckily it doesn't require much prior knowledge of chemistry to understand this concept and to see what type of bonding might exist between certain atoms.

Firstly, if a metal and a nonmetal react, then the nonmetal typically gains electrons from the metal. This turns the metal into a positive ion (cation), and the nonmetal becomes a negative ion (anion). This bonding is called ionic bonding because the atoms exist as ions. An example is NaCl, common table salt. Because sodium gives one electron to the chlorine atom, they are both ions and share an ionic bonding. Therefore, an easy rule to remember is that if the atoms have opposite charges, they will most likely form an ionic bond.

Secondly, there is covalent bonding. Covalent bonding usually occurs when atoms exist as diatomic molecules, meaning two atoms of the same element bond together in one unit. The atoms share the electrons equally in a bond, and there is no electron transfer. An example of covalent bonding is when two hydrogen atoms bond together. They both need one more electron to complete their outer shell, so they share this electron equally among them. An easy rule of thumb for covalent bonding is that most nonmetals get a covalent bond when they react with an atom of the same element.

Finally, there is a polar covalent bond. The idea is similar to a covalent bond, but here one of the atoms attracts the electrons more strongly than the other. To visualize a polar covalent bond consider two atoms, for example hydrogen and fluorine. Fluorine has a much stronger electronegativity than hydrogen, or fluorine wants an electron much more than hydrogen, so the shared electrons will be pulled much closer to the fluorine atom. This creates a polar covalent bond where the bonds are not shared equally. There is a negative side of the molecule, the fluorine, and a positive, the hydrogen. Usually whenever two different nonmetals react they will have a polar covalent bond.

The three most typical chemical bonds are simplified in this text, but it should be enough to tell what kind of bond a molecule will have. If in doubt about an atom being a metal or nonmetal, look at the periodic table. The elements on the far right are nonmetals, the rest are metals.