By treating quick lime with water calcium Hydroxide is obtained.
Properties
1. Physical nature
Calcium Hydroxide is a white amorphous powder.
2. Solubility in water
It is very sparingly soluble in water. The solubility is only 0.19 g/100g of water at 32oF.
3. On strong heating it gets dehydrated to form quicklime and water.
5. Calcium Hydroxide reacts with ammonium salts when heated, to form ammonia gas, and water vapor.
Uses
1. Calcium hydroxide is used in the preparation of lime water. Lime water is a saturated solution of calcium hydroxide in water.
2. It is used to make milk of lime for white washing. When a small quantity of water is mixed with slaked lime, milk of lime paste is formed. It is used for white washing.
3. Used for making lime mortar.
4. It is used to remove temporary hardness in water softening.
5. It is used to neutralize the acidity of the soil. A calculated quantity of slaked lime is added to the soil to neutralize the soil. Besides, it also provides calcium salts needed for the plants.
6. Calcium hydroxide is used in the manufacture of bleaching powder.
7. It is used in the leather industry for de-haring of the hides of animals.
Remember :
Preparation of Lime Water
Take a large quantity of water. Add a small quantity of slaked lime. Stir well. Keep the vessel covered, so as to avoid carbon dioxide of the air reacting with the liquid. Allow the water to stand for a few hours. The slaked lime that has not dissolved will settle down. Decant the clear liquid into another vessel. This clear liquid is lime water. It is used to detect the presence of carbon dioxide.
