A hardened limestone becomes brittle at high temperatures"Chemical formula: CaCO3= = =CaO+CO2 at high temperatureExperimental phenomena: the burnt limestone becomes whiter and easier to crushApplication: calcined limestone to obtain quicklime
Three: powdered lime in the air becomes "hard"Chemical formula: Ca (OH) 2+CO2=CaCO3: +H2OExperimental phenomena: carbon dioxide gas into the clarified lime water, the solution becomes turbid
Two change: a large block of raw lime in water change "crisp"Chemical equation: CaO+H2O=Ca (OH) 2Experimental phenomenon: a large number of fog, a large amount of heat, bulk solids into a powder like solidApplication: (1) will be used for lime desiccant, used for drying gas. Because lime can react with water, carbon dioxide and other substances, so the lime should (seal) preservation, also cannot use it to dry carbon dioxide, hydrogen chloride gas.(2) when quicklime reacts with water, it gives off a large amount of heat, which causes the water to boil,
Two change: a large block of raw lime in water change "crisp"Chemical equation: CaO+H2O=Ca (OH) 2Experimental phenomenon: a large number of fog, a large amount of heat, bulk solids into a powder like solidApplication: (1) will be used for lime desiccant, used for drying gas. Because lime can react with water, carbon dioxide and other substances, so the lime should (seal) preservation, also cannot use it to dry carbon dioxide, hydrogen chloride gas.
