JEE Advanced2017ChemistryCoordination CompoundsActual
Addition of excess aqueous ammonia to a pink coloured aqueous solution of M C l 2 . 6 H 2 O ( X ) and N H 4 C l gives an octahedral complex Y in the presence of air. In aqueous solution, complex Y behaves as 1 : 3 electrolyte. The reaction of X with excess HCl at room temperature results in the formation of a blue coloured complex Z. The calculated spin only magnetic moment of X and Z is 3.87 B.M., whereas it is zero
Options
- AWhen X and Z are in equilibrium at 0°C, the colour of the solution is pink
- BThe hybridization of the central metal ion in Y is d 2 s p 3
- CZ is atetrahedral complex
- DAddition of silver nitrate to Y gives only two equivalents of silver chloride
Correct answer
A. When X and Z are in equilibrium at 0°C, the colour of the solution is pink
Step-by-step solution
Cobalt salts are pink in anhydrous & blue in hydrated form (i) Hybridisation of (Y) is d 2 s p 3 as N H 3 is a strong field ligand (ii) C o C l 4 2 - have s p 3 hybridisation as C l - is a weak field ligand (iii) (iv)