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salt 09 Heating limestone (quicklime) and "watering" (slaked lime)

Quicklime and slaked lime are very corrosive: Goggles and gloves needed!

* Left: A piece of marble very pure calciumarbonate (CaCO₃).
* Photo 2:  0.5 g marble are are placed on a tile and heated by a butan gas micro burner for 15 minutes.
Observations: The stone loses it crystaline shine. Its mass is reduced from 0.5 g to 0.3 g.
Explanation:
A chemical reaction ("burning")took place, a new substance (quick lime = Calcium oxide) is formed:        CaCO₃ --------consumption of heat-----------> CaO  +  CO₂
Photo 3 and 4: Quick lime (prepared for agriculture) is mixed with water:
* Observation Photo 3:  The water is soaked up. Steam is built as the powder swells and produces a lot of heat.  
* Explanation: This chemical reaction (slaking lime), leaves calcium hyroxide.