Boiling chips are small, irregularly shaped stones added to liquids to make them boil more smoothly. They provide nucleation sites so the liquid boils easily without becoming superheated. Without boiling chips, a liquid being heated in a smooth container can become superheated and "bump" in a sudden, sometimes violent release of vapor.

Boiling chips are typically made of a porous material, such as alumina, calcium carbonate or carbon, and often have a nonreactive coating of Teflon (PTFE). This ensures that the boiling chips will provide effective nucleation sites, yet be chemically inert.

Never add boiling chips to an already hot liquid, as it could cause a large amount of vapor to form all at once. This could cause hot liquid to be expelled from the container, possibly causing heat or chemical burns Laboratory equipment | Phase changes