Plaster of Paris, ( CaSO4 . ½ H2O) Plaster of Paris is calcium sulphate hemihydrate, CaSO4 . ½ H2O . Preparation of Plaster of Paris It is prepared by heating gypsum to 393 K. 2 CaSO4 . 2 H2O ---------> 2 CaSO4 . ½ H2O + 3 H2O The following conditions are necessary: 1) The temperature should not be allowed to rise above 393 K because above this temperature, the … [Read more...] about Plaster of Paris
Chemistry
Calcium Carbonate
Calcium Carbonate , CaCO3 Calcium carbonate is also called limestone. It occurs in nature as Chalk, marbles, corals, calcite. Mixed with magnesium carbonate it occurs as dolomite. Preparation of Calcium Carbonate 1) From slaked lime It can be prepared by passing a calculated quantity of CO2 through slaked lime. Ca(OH)2+ CO2 ------> CaCO3 ↓ + H2O 2) From calcium … [Read more...] about Calcium Carbonate
Calcium Hydroxide
Preparation of Calcium Hydroxide From quick lime Calcium hydroxide is prepared on a commercial scale by adding water to quicklime. This process is called slaking of lime. CaO + H2O ----> Ca(OH)2 From calcium chloride It is also obtained by treating calcium chloride with caustic soda. Properties of Calcium Hydroxide 1) It is a white amorphous powder … [Read more...] about Calcium Hydroxide
Calcium Oxide
Calcium Oxide Preparation of Calcium Oxide Calcium oxide is called quick lime. It is prepared by heating limestone in a rotatory kiln at 1070-1270 K. CaCO3 ⇔ CaO + CO2 ΔH = 179.9 KJ Since the reaction is reversible, therefore, the carbon dioxide is removed as soon as it is formed to enable the reaction to proceed to completion. The temperature is not allowed to … [Read more...] about Calcium Oxide
Uses of Alkaline Earth Metals
Beryllium 1) It is used in the manufacture of alloys. Copper-beryllium alloys are used in the preparation of high strength springs. 2) Metallic beryllium is used for making Windows of X- ray tubes. Magnesium 1) It is used to prepare alloy with aluminium, zinc , manganese and tin. 2) Magnesium - aluminium alloy being light in mass are used in construction of … [Read more...] about Uses of Alkaline Earth Metals