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Function and Importance of Chemical Bonds: Ionic, Covalent, and Metallic

By Dawn Marcotte

Chemical bonds combine different elements to make up new forms. There are seven different types of chemical bonds. Learn all seven types here.

There are currently 118 different elements on the periodic table. Without chemical bonds there would only be 118 different materials in the world. There are seven kinds of chemical bonds that have been identified so far by the scientific community. Each of these bonds creates compounds that have specific characteristics and differences in strengths. These compounds each have their own uses and characteristics, but without chemical bonding they could not exist.

The chemical bonds are:

  1. ionic
  2. metallic
  3. covalent
  4. polarized
  5. hydrogen
  6. van der Waals
  7. clathrate

The most important of these are the ionic, covalent and metallic bonds. In each of these bonds electrons are shared between elements. Electrons orbit atoms in layers or shells according to the type of element. Different types of bonds share these electrons in a different way.

Ionic Bonds

salt flats 

These chemical bonds are created between ions where one is a metal and one is a non-metal element. Ions are atoms with a number of electrons that does not match the number of protons. Individual electrons in the outside shell are shared between the two elements, but one of the elements will have a stronger pull on the shared electron.

An example of this type of bonding is table salt, also known as sodium chloride. Ionic bonds are made between a metal (sodium) and non-metal (chloride) to create a solid that has a very high boiling or melting point. At room temperature these types of bonds form solids. These compounds can be dissolved in water to break the bond. An example is dissolving salt in water. Once dissolved the liquid is able to conduct electricity. Ionic bonds form many compounds used every day.

Covalent Bonds

Covalent bonds occur between two non-metal elements such as Carbon and Hydrogen to form gases such as Methane (CH4) or liquids such as Hydrochloric Acid. The electrons in the outside shell are shared equally in pairs between the two metals. The bonds between the two elements are weak because each element pulls equally on the shared electrons, so they form materials that have a low boiling or melting point. These compounds are either gas or liquid at room temperature. They do not dissolve easily in water and do not easily conduct electricity.

Metallic Bonds

Gold is an example of a metallic bond 

Most of the elements on the periodic table are actually metallic. When these elements combine it creates a metallic bond. Metallic bonds allow the elements to conduct electricity, they can be formed into shapes and they conduct heat easily. This is the strongest of the three major bonds because the electrons are shared in more than just the first shells. The more shells involved in sharing electrons, the stronger the bond. Compounds formed by metallic bonds do not completely break until the metal is boiled, usually at a very high temperature. Steel is an example of a metallic bond. Without metallic bonds and the properties of metal modern life would not be possible. Steel is used extensively in every modern society. Metal is also used in electronics that form the basic components in computers and other essential modern conveniences.

Other Chemical Bonds

The other bonds are not nearly as strong as these first three. Van der Waals and clathrate are bonds between molecules, not atoms as the other types of bonds. Hydrogen bonds refer specifically to the types of bonds formed with hydrogen atoms, such as the water in sweat. Polarized bonds form when two atoms share an electron, but one of the elements has a stronger attraction to that shared electron.

Chemical bonds allow all of the elements to combine in a variety of ways to create everything on Earth. Without these chemical bonds life as we know it would not be able to exist as every living organism is created from compounds of elements that work together in specific ways.