From the figure of column chromatography given below, identify incorrect statements. (A) Compound ' c ' is more polar…

Step 1: Understand Column Chromatography Principles

In column chromatography using a polar adsorbent (silica gel/alumina):

• Most polar compound → strongest adsorption → travels slowest → remains highest in the column → elutes last
• Least polar compound → weakest adsorption → travels fastest → exits column first

From the figure, three compounds a, b, c are separated where 'c' is at the bottom (eluted first), then 'b', and 'a' is at the top (eluted last).

Step 2: Evaluate Statement (A)

"Compound 'c' is more polar than 'a' and 'b'" ❌

False. 'c' elutes first (exits the column first) → weakest adsorption → least polar among the three. Statement A has it backwards.

Step 3: Evaluate Statement (B)

"Compound 'a' is least polar" ❌

False. 'a' is at the top of the column (retained longest, elutes last) → strongest adsorption → most polar compound. Statement B is incorrect.

Step 4: Evaluate Statement (C)

"Compound 'b' comes out before 'c' and after 'a'" ❌

False. From the column figure: c elutes first, b elutes second, a elutes last. So b comes out AFTER c (not before c). Statement C is also incorrect.

Step 5: Evaluate Statement (D)

"Compound 'a' spends more time in the column" ❌

False. 'a' is the most polar → strongest adsorption → moves slowest → YES, it spends the most time in the column. Wait — this is actually TRUE! So Statement D is correct.

Summary: Incorrect statements are A, B, C

Answer: (A), (B) and (C) only → Option (c)

Key Points to Remember:

• Elutes first = least polar = weakest adsorption = lowest in column (exits first)
• Elutes last = most polar = strongest adsorption = highest in column (exits last)
• More time in column = slower movement = stronger adsorption = more polar
• The compound at the bottom of the column band has already moved the most → less polar