- The material world is bound together by chemical bonds, which determine the structure, size and characteristics of chemical compounds.
- A chemical compound consists of two or more atoms from different elements that are chemically bonded together.
- Chemical bonds occur because the electromagnetic force operates between charged particles.
- Opposite charges attract one another and like charges repel.
- The higher the charge, the stronger the force.
- There are different types of chemical bonds. Each affects the physical and chemical properties of a compound, including reactivity, melting point, boiling point, and electrical conductivity.
The most common types of chemical bonds are:
Covalent Bonds
- Covalent bonds occur when electrons are shared between two atoms. The shared electrons are attracted to the protons of both nuclei, which keeps the atoms bonded together.
Ionic Bonds
- Ionic bonds occur when one atom completely transfers one or more electrons to another atom. This creates ions, with the atom that loses electrons becoming a positively charged ion and the atom that gains electrons becoming a negatively charged ion. The attraction between these opposite charges keeps the ions bonded together.
Metallic Bonds
- Metallic bonds are found in metals; they consist of the electrostatic attractive force between the conduction electrons, in what is known as an electron cloud, and the positively charged metal ions. These bonds allow for characteristics such as high melting points, malleability, and conductivity.
Hydrogen Bonds
- Hydrogen bonds are a type of dipole-dipole interaction that happens when a hydrogen atom bonded to a strongly electronegative atom (like nitrogen, oxygen, or fluorine) is also attracted to another electronegative atom in the same or another molecule.