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Heat the mixture. Ammonium chloride sublimes and is collected as a sublimate leaving sodium chloride and copper (II) oxide. Add water to the mixture and stir. Filter to obtain copper (II) oxide as the residue and sodium chloride as the filtrate. Evaporate the filtrate to saturation to get crystals of sodium chloride.
raphael answered the question on January 31, 2017 at 12:47
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