JEE Main · 2025 · 28 Jan 2025 · Shift 2 · Practical and Analytical Chemistry

The purification method based on the following physical transformation is :

(A)Sublimation✓ Correct
(B)Distillation
(C)Crystallization
(D)Extraction

Answer: (A)

Solution

The scheme shows a solid X converting to vapour on heating and condensing directly back to solid X on cooling, with no liquid stage in between. A phase change that bypasses the liquid state entirely is sublimation, used to purify substances such as iodine, camphor, naphthalene and benzoic acid away from non-volatile impurities that do not sublime.

JEE Main · 2025 · 28 Jan 2025 · Shift 2 · Single correct option

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