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Give preparation, properties and uses of Calcium oxide or quick lime (CaO). |
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Answer» Solution :It is prepared on a commercial scale by HEATING limestone `(CaCO_(3))` in a ROTARY kiln at 1070-1270 K. `CaCO_(3)overset("heat")hArr CaO+CO_(2)` The carbon dioxide is removed as soon as it is produced to enable the reaction to proceed to COMPLETION. Properties : Calcium oxide is a white amorphous solid. It has a melting point of 2870 K. On exposure to atmosphere, it absorbs moisture and carbon dioxide. `CaO+H_(2)O to Ca(OH)_(2)` `CaO+CO_(2) to CaCO_(3)` The addition of limited amount of water breaks the lump of lime. This process is called slaking of lime. Quick lime slaked with soda gives solid sodalime. Being a basic oxide, it combines with acidic oxides at high temperature. `CaO+SiO_(2) to CaSiO_(3)` `6CaO+P_(4)O_(10) to 2Ca_(3)(PO_(4))_(2)` |
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