Molecule

Definition

A molecule is a group of two or more atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction. Molecules can consist of atoms of the same element, like O2, or different elements, like H2O.

5 Must Know Facts For Your Next Test

1. Molecules are held together by covalent bonds, which involve the sharing of electron pairs between atoms.
2. Water (H2O) is a common example of a molecule essential for life.
3. Molecules can have various shapes and sizes, determining their function and properties.
4. Biological molecules include carbohydrates, lipids, proteins, and nucleic acids.
5. The arrangement of atoms within a molecule dictates its chemical behavior and interaction with other molecules.

Review Questions

• What type of bond holds the atoms in a molecule together?
• Give an example of a molecule and explain its importance in biology.
• How does the arrangement of atoms within a molecule affect its properties?

Related terms

Atom: The basic unit of matter consisting of protons, neutrons, and electrons.

Covalent Bond: A type of chemical bond where two atoms share one or more pairs of electrons.

Compound: A substance formed when two or more different types of atoms bond together chemically.