JEE Main20262 April 2026Morning ShiftChemistryp Block Elements (Group 15, 16, 17 & 18)Actual
Given below are two statements : Statement (I) : Oxidising power of halogens decreases in the order F₂ > Cl₂ > Br₂ > I₂ , which is the basis of "Layer test". Statement (II) : "Layer test" to identify Br₂ and I₂ in aqueous solution involves the oxidation of bromide or iodide into Br₂ or I₂ respectively with Cl₂ , which is a type of displacement redox reaction. In the light of the above statements, choose the correct a
Options
- ABoth Statement I and Statement II are true
- BBoth Statement I and Statement II are false
- CStatement I is true but Statement II is false
- DStatement I is false but Statement II is true
Correct answer
A. Both Statement I and Statement II are true
Step-by-step solution
Statement I is true. The oxidising power of halogens decreases down the group in the order F₂ > Cl₂ > Br₂ > I₂ . A stronger oxidising halogen can displace a weaker oxidising halogen from its aqueous halide solution. This principle forms the basis of the layer test. Statement II is true. In the layer test, chlorine water ( Cl₂ ) is added to an aqueous solution containing bromide ( Br^- ) or iodide ( I^- ) ions. Since Cl₂ is a stronger oxidising agent, it oxidises Br^- to Br₂ and I^- to I₂ . The reaction is given by: