JEE Main · 2026 · 23 Jan 2026 · Shift 2 · d and f Block Elements

The oxidation state of chromium in the final product formed in the reaction between KI and acidified

K_{2} Cr_{2} O_{7}

solution is:

Answer: (B)

Solution

In acidic medium dichromate is a strong oxidant and oxidises iodide to iodine,

C r_{2} O_{7}^{2 -} + 14 H^{+} + 6 I^{-} \to 2C r^{3 +} + 3 I_{2} + 7 H_{2} O

. In being reduced, chromium falls from

+ 6

in dichromate to

+ 3

in the product. The oxidation state of chromium in the final product is

+ 3

JEE Main · 2026 · 23 Jan 2026 · Shift 2 · Single correct option