MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

The given reaction is 3 H _3 AsO _ 3(aq) + BrO _ 3(aq) ^- Br _ (aq) ^- + 3 H _3 AsO _ 4(aq) Let the oxidation state of As in H _3 AsO _3 be x. 3(+1) + x + 3(-2) = 0 x = +3 Let the oxidation state of Br in BrO _3^- be y. y + 3(-2) = -1 y = +5 Let the oxidation state of As in H _3 AsO _4 be z. 3(+1) + z + 4(-2) = 0 z = +5 The oxidation state of Br in Br ^- is -1. The oxidation state of As increases from +3 to +5, so H _3 AsO _3 undergoes oxidation and acts as a reducing agent. The oxidation state of Br decreases from +5 to -1, so BrO _3^- undergoes reduction and acts as an oxidising agent. The change in oxidation state of the oxidising agent is +5 to -1. Answer: +5\ to \ -1