An octahedral complex having molecular composition $\mathrm{Co} .5 \mathrm{NH}_{3} . \mathrm{Cl} . \mathrm{SO}_{4}$ has two isomers A and B . The solution of A gives a white precipitate with $\mathrm{AgNO}_{3}$ solution and the solution of B gives white precipitate with $\mathrm{BaCl}_{2}$ solution. The type of isomerism exhibited by the complex is,

JEE Main · 2025 · 07 Apr 2025 · Shift 1 · Coordination Compounds

An octahedral complex having molecular composition

Co .5 NH_{3} . Cl . SO_{4}

has two isomers A and B . The solution of A gives a white precipitate with

AgNO_{3}

solution and the solution of B gives white precipitate with

BaCl_{2}

solution. The type of isomerism exhibited by the complex is,

(A)Co-ordinate isomerism
(B)Linkage isomerism
(C)Ionisation isomerism✓ Correct
(D)Geometrical isomerism

Answer: (C)

Solution

The composition

C o \cdot 5 N H_{3} \cdot C l \cdot S O_{4}

can keep either chloride or sulphate inside the coordination sphere. In one form,

[C o (N H_{3})_{5} S O_{4}] C l

, the free chloride gives a white precipitate of silver chloride with silver nitrate; in the other,

[C o (N H_{3})_{5} C l] S O_{4}

, the free sulphate gives a white precipitate of barium sulphate with barium chloride. Isomers that differ by exchange of an ion between the coordination sphere and the counter-ion position display ionisation isomerism.

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

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JEE Main · 2025 · 07 Apr 2025 · Shift 1 · Coordination Compounds

Solution

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