WAEC Chemistry 2025 Paper

Concept:Sublimation separates a volatile solid from a non‑volatile solid.Explanation:When the mixture is heated, iodine ($\mathrm{I}_2$) sublimes directly into purple vapour.Calcium chloride ($\mathrm{CaCl}_2$) does not sublime, so it remains behind as a solid residue.The iodine vapour is then cooled and collected as pure solid iodine.This leaves calcium chloride separately in the original container.Answer:B. Sublimation