JAMB Chemistry 2019 Paper

Concept:Use differences in solubility and sublimation to separate a solid mixture.Explanation:Sodium chloride dissolves in water, while sand and iodine do not.Add water to the mixture and stir. Sodium chloride dissolves.Filter the mixture. The filtrate is salt solution; the residue is sand and iodine.Evaporate the filtrate to dryness. Sodium chloride remains as solid crystals.Heat the residue gently. Iodine sublimes, leaving sand behind.So the correct operations are: addition of water $\rightarrow$ filtration $\rightarrow$ evaporation to dryness $\rightarrow$ sublimation.Answer:A. addition of water, filtration, evaporation to dryness and sublimation