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Kstab ? chemistry (OCR) A2

Hi, I was wondering if anyone knew the definition for Kstab - the stability complex?

My CGP revision book says the 'Kstab of a complex ion is the equilibrium constant for the formation of a complex ion from its contituent ions in solution'
It says you can find the Kstab for the formation of a complex ion from ions and for ligand substitution reactions.

But my textbook says Kstab is the equilibrium constand for the ligand substitution of a complex ion with water ligands.

I don't know which is right :frown:
Original post by Gemma2010
Hi, I was wondering if anyone knew the definition for Kstab - the stability complex?

My CGP revision book says the 'Kstab of a complex ion is the equilibrium constant for the formation of a complex ion from its contituent ions in solution'
It says you can find the Kstab for the formation of a complex ion from ions and for ligand substitution reactions.

But my textbook says Kstab is the equilibrium constand for the ligand substitution of a complex ion with water ligands.
2 h
I don't know which is right :frown:


Stability constants measure the relative stability of ligands in a complex ion

For the complex ion:

[Ni(NH3)6]2+ in solution there wil be some tendency for the ligands to exchange with water molecules:

[Ni(NH3)6]2+ + H2O <==> [Ni(NH3)5(H2O)]2+ + NH3

The equilibrium constant for this reaction is the stability constant:

Kstab = [[Ni(NH3)5(H2O)]2+][NH3]/[[Ni(NH3)6]2+]
Original post by charco

Original post by charco
Stability constants measure the relative stability of ligands in a complex ion

For the complex ion:

[Ni(NH3)6]2+ in solution there wil be some tendency for the ligands to exchange with water molecules:

[Ni(NH3)6]2+ + H2O &lt;==&gt; [Ni(NH3)5(H2O)]2+ + NH3

The equilibrium constant for this reaction is the stability constant:

Kstab = [[Ni(NH3)5(H2O)]2+][NH3]/[[Ni(NH3)6]2+]


Cheers :biggrin:

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