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Calcination and slaking of lime

Short answer

Calcination is the burning of limestone at 900–1000°C to drive off CO₂ and produce quicklime (CaO). Slaking is the addition of water to quicklime, causing a vigorous reaction with heat and expansion, forming slaked lime (Ca(OH)₂).

What do you mean by calcination and slaking (hydration) of lime?

Calcination

Calcination is the burning of limestone at 900 to 1000 °C in a kiln, which drives off carbon dioxide and gives quicklime.

CaCO3→ 900∘C CaO+CO2\text{CaCO}_3 \xrightarrow{\ 900^\circ\text{C}\ } \text{CaO} + \text{CO}_2

Slaking (hydration)

Slaking is the addition of water to quicklime. It reacts violently, gives out heat, swells to 2 to 2.5 times its volume and turns into slaked lime (calcium hydroxide) in powder or paste form.

CaO+H2O→Ca(OH)2+heat\text{CaO} + \text{H}_2\text{O} \rightarrow \text{Ca(OH)}_2 + \text{heat}

✓ Answer checked by Claude Opus 5.5 (high effort)

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