Three moles of AgCl get precipitated when one mole of an octahedral co-ordination compound with empirical formula reacts with excess of silver nitrate. The number of chloride ions satisfying the secondary valency of the metal ion is ______.
Answer: 0
Solution
Silver nitrate precipitates only the chloride that is free in solution, that is the chloride held by the primary valency outside the coordination sphere. Three moles of silver chloride per mole of complex therefore means all three chlorides are ionisable counter ions and none is attached to the metal. The chromium(III) centre is octahedral, so its six secondary valencies must be taken up by the three ammonia and the three water molecules, and the compound is . The number of chloride ions satisfying the secondary valency is .
JEE Main · 2021 · 25 Jul 2021 · Shift 1 · Integer answer