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Topic: Metal Complexes Conundrum  (Read 1683 times)

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Offline ComplexInterest

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Metal Complexes Conundrum
« on: February 21, 2016, 08:02:04 PM »
     I noticed that in the reversible reaction Fe³⁺(aq) + SCN(aq) ⇌ FeSCN²⁺(aq) the addition of SCN moves the equilibrium more to the right than the addition of Fe³⁺(The addition of 1 mol of SCN will redden the solution more than the addition of 1 mol of Fe³⁺).
     I take this is due to the nature of metal complexes, but I'm not quite sure what exactly is the reason that the addition of a ligand molecule has more effect than the addition of a donor atom. Any help is appreciated.

Offline AWK

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Re: Metal Complexes Conundrum
« Reply #1 on: February 21, 2016, 08:11:04 PM »
You answered for your question at the beginning - this is equilibrium (with relatively low constant of formation).
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Offline Borek

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Re: Metal Complexes Conundrum
« Reply #2 on: February 22, 2016, 03:23:22 AM »
What are the initial concentrations?

Calculate concentration of the complex for each case, this is relatively easy equilibrium problem.
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