The first transition series metal 'M' has the highest enthalpy of atomisation in its series. One of its aquated ion ($\mathrm{M}^{\mathrm{n}+}$) exists in green colour. The nature of the oxide formed by the above $\mathrm{M}^{\mathrm{n}-}$ ion is :

JEE Main · 2025 · 07 Apr 2025 · Shift 1 · d and f Block Elements

The first transition series metal 'M' has the highest enthalpy of atomisation in its series. One of its aquated ion (

M^{n +}

) exists in green colour. The nature of the oxide formed by the above

M^{n -}

ion is :

Answer: (C)

In the first transition series the enthalpy of atomisation is greatest for vanadium, so the metal is vanadium. The green aquated ion of vanadium is

V^{3 +}

, whose oxide is

V_{2} O_{3}

. A metal oxide in a low oxidation state such as

+ 3

is basic in nature. The oxide is basic.

JEE Main · 2025 · 07 Apr 2025 · Shift 1 · Single correct option