noun, plural: chemical bonds
A chemical bond is a bond that holds atoms together. It is the force that binds ions or molecules together. It helps form a chemical compound. Examples of the chemical compounds that are of special interest to biologists are water, sodium chloride, and carbon dioxide. These chemical compounds are formed by the chemical bond that binds the constituent atoms. For instance, water is comprised of two hydrogen atoms and an oxygen connected by chemical bonds.
There are three types of chemical bonds that are biologically important: (1) ionic bonds, (2) covalent bonds, and (3) hydrogen bonds. The ionic bond is a type of chemical bond in which there is a complete transfer of an electron from one atom to another. An example is the sodium chloride, which is made up of a cation (Na+) and an anion (Cl-). The two ions of sodium chloride are held together by an ionic bond. A covalent bond is a type of a chemical bond wherein electrons are shared between atoms. The bond between hydrogen and oxygen atoms to form water is an example of a covalent bond. The hydrogen bond is a low-energy electrostatic bond wherein hydrogen serves as a bridge between two atoms.