What prefix is used to denote four atoms in a chemical compound?

In chemistry, the prefix that denotes four atoms in a chemical compound is "Tetra." This prefix is derived from Greek and is commonly used in naming various compounds, especially in organic and inorganic chemistry. For instance, you may encounter terms like "tetrachloride," indicating a compound that contains four chlorine atoms, or "tetramer," which refers to a molecular structure composed of four repeating units.

The prefixes used in chemical nomenclature serve to convey specific information about the number of atoms or groups present in a molecule, allowing for clear communication among scientists and students.