- Secure a piece of chalk in a jaw clamp of a laboratory stand.
- Heat the piece of chalk with a burner. A few minutes later the piece glows brilliant white light.
Chalk lights under heating
Scientific name: Calcium carbonate decomposes under heating and the formed calcium oxide emits white light
Wear eye protection and lab gloves.
Always follow general safety recommendations. Please note that conducting chemistry experiments you must comply with the relevant legal procedures in your country.
CaCO3 -[T]→ CaO + CO2
Chalk consists of calcium carbonate. It decomposes under heating to form calcium oxide and carbon dioxide. Calcium oxide (or quicklime) luminesces at a high temperature - heated quicklime emits photons of white light, and the energy of heat converts to the energy of light.