Sun, 03 May 2026 14:58:46 +0000

Pouring Water on Calcium Oxide: The Burning Secret Everyone Guards Silently When calcium oxide – also known as quicklime – is poured onto water, something extraordinary happens: a violent exothermic reaction occurs, releasing intense heat and emitting a bright flash of light. Though seemingly simple, this chemical interaction remains one of the most potent and cautiously whispered secrets in industrial and laboratory settings. The burning process of calcium oxide and water, often guarded silently due to its volatility, is a critical reaction that powers numerous applications while demanding strict safety measures. ### The Chemistry Behind the Splash Calcium oxide (CaO), a strong alkaline compound widely used in construction, metallurgy, and chemical manufacturing, reacts violently with water (H₂O). When water is added to quicklime, the reaction produces calcium hydroxide (Ca(OH)₂) and releases a tremendous amount of heat—often exceeding 500°C (932°F). The immediate exothermic release generates steam and can ignite nearby flammable materials, contributing to the perception of a “burning” incident.