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chemistry lab
Submitted by Anonymous on 8 February 2005 - 7:01am.
You have two solid texture that contains calcium carbonate and potassium bromide. propose a method to separate these two solids. |
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CaCO3 is a fairly insoluble white solid while KBr is a clear ionic solid very soluble in H2O. put the mixture in a cone of filter paper and pour cold water in it; the H2O will leach out the KBr and leave the CaCO3 behind.
you could bring the temperature to about 750-800 C and pour the liquid KBr
off. note that calcium carbonate decomposes at 899 C
OR bring the temperature up to about >1500, that would boil off the KBr decompose the calcium carbonate to calcium oxide.
you could collect the KBr on a cooler surface away from the heat source to retrieve it. Then add water to Calcium oxide to react it to Ca(OH)2, get rid of the exces water and expose the Ca(OH)2 to CO2 to get your CaCO3 back
well jeez, if you have a vessel/system that is capable of +1500C, why not just add an overpressure of CO/CO2 inside the vessel to directly react the CaO + CO/CO2 ---> CaCO3.