Chemical Bonding in Organic Molecules

Chemical Bonding in Organic Molecules

Key Points

• Organic molecules are composed of carbon atoms bonded to each other and to other elements (primarily hydrogen, oxygen, nitrogen, and halogens).
• The most common types of chemical bonds in organic molecules are covalent bonds.
• Covalent bonds form when two atoms share a pair of electrons.
• The strength of a covalent bond depends on the number of shared electrons and the electronegativity of the atoms involved.
• Organic molecules can exhibit ionic bonding, hydrogen bonding, and dipole-dipole interactions in addition to covalent bonding.

Main Concepts

Covalent bonding is the primary type of chemical bonding in organic molecules. A covalent bond forms when two atoms share an electron pair. The electrons are attracted to the nuclei of both atoms, which holds the atoms together.

The strength of a covalent bond depends on the number of shared electrons and the electronegativity of the atoms involved. Electronegativity is a measure of an atom\'s ability to attract electrons. The more electronegative an atom, the more strongly it will attract the shared electrons in a covalent bond.

In addition to covalent bonding, organic molecules can also exhibit ionic bonding, hydrogen bonding, and dipole-dipole interactions. Ionic bonding occurs when an atom transfers an electron to another atom, resulting in the formation of two oppositely charged ions. Hydrogen bonding occurs when a hydrogen atom is bonded to a highly electronegative atom, such as oxygen or nitrogen. Dipole-dipole interactions occur when two polar molecules interact with each other.

The types of chemical bonding present in an organic molecule determine its physical and chemical properties. For example, molecules with strong covalent bonds are generally more stable than molecules with weak covalent bonds. Molecules with ionic bonds are generally more soluble in water than molecules with covalent bonds.