' X ' is the number of acidic oxides among $\mathrm{VO}_{2}$, $\mathrm{V}_{2} \mathrm{O}_{3}, \mathrm{CrO}_{3}, \mathrm{~V}_{2} \mathrm{O}_{5}$ and $\mathrm{Mn}_{2} \mathrm{O}_{7}$. The primary valency of cobalt in $\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{NCH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}\right)_{3}\right]_{2}\left(\mathrm{SO}_{4}\right)_{3}$ is Y . The value of $\mathrm{X}+\mathrm{Y}$ is :

JEE Main · 2025 · 07 Apr 2025 · Shift 2 · Coordination Compounds

' X ' is the number of acidic oxides among

VO_{2}

V_{2} O_{3}, CrO_{3}, V_{2} O_{5}

and

Mn_{2} O_{7}

. The primary valency of cobalt in

[Co (H_{2} NCH_{2} CH_{2} NH_{2})_{3}]_{2} (SO_{4})_{3}

is Y . The value of

X + Y

is :

(A)5✓ Correct
(B)4
(C)2
(D)3

Answer: (A)

Solution

Acidic oxides are formed by a metal in a high oxidation state. Among the given set,

Cr O_{3}

(chromium in

+ 6

) and

M n_{2} O_{7}

(manganese in

+ 7

) are acidic, while

V_{2} O_{5}

and

V O_{2}

are amphoteric and

V_{2} O_{3}

is basic, so the number of acidic oxides is

X = 2

. In

[Co (en)_{3}]_{2} (S O_{4})_{3}

each cobalt is

C o^{3 +}

, and the primary valency is just the oxidation state, so

Y = 3

. Adding these,

X + Y = 5

JEE Main · 2025 · 07 Apr 2025 · Shift 2 · Single correct option

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