Advanced Placement (AP) Chemistry Practice Exam

What type of bond involves the sharing of electrons between two atoms?

1. Ionic bond

2. Covalent bond

3. Metallic bond

4. Hydrogen bond

The correct answer is: Covalent bond

A bond that involves the sharing of electrons between two atoms is known as a covalent bond. In a covalent bond, atoms share pairs of electrons to achieve a full valence shell and stabilize their electronic configuration. This sharing can be equal, resulting in a nonpolar covalent bond, or unequal, leading to a polar covalent bond, depending on the electronegativity differences between the atoms involved. Ionic bonds, on the other hand, involve the transfer of electrons from one atom to another, resulting in the formation of charged ions. Metallic bonds are characterized by a 'sea of electrons' where electrons are delocalized and can move freely among a lattice of metal atoms. Hydrogen bonds are a type of weak interaction that occurs between a hydrogen atom bonded to an electronegative atom and another electronegative atom. These interactions are important in biological molecules like water and DNA but do not involve the sharing of electrons in the same way as covalent bonds.