KCN+FeCl3 (aq) = Ferricyanide complex form

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srinimag
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KCN+FeCl3 (aq) = Ferricyanide complex form

Post by srinimag »

I DON’T GET THIS!

If KCN is added to an aqueous FeCl3 solution will ferricyanide complex form?

If KCN (potassium cyanide) is added to an aqueous FeCl3 (ferric chloride) solution, ferricyanide complex (Fe(CN)6)3- is not expected to form.

The addition of KCN to an aqueous solution of FeCl3 will cause the formation of a complex between Fe3+ and cyanide ion (CN-) as follows:

Fe3+ + CN- ⇌ Fe(CN)63-

This complex is known as ferricyanide and has a characteristic red color. However, this complex formation requires the presence of ferrous ion (Fe2+) in the solution, which acts as a reducing agent and reduces Fe3+ to Fe2+. In the absence of Fe2+, ferricyanide complex formation is not expected to occur.

Therefore, if KCN is added to an aqueous FeCl3 solution in the absence of Fe2+, ferricyanide complex is not expected to form.
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ChenBeier
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Re: KCN+FeCl3 (aq) = Ferricyanide complex form

Post by ChenBeier »

However, this complex formation requires the presence of ferrous ion (Fe2+) in the solution, which acts as a reducing agent and reduces Fe3+ to Fe2+. In the absence of Fe2+, ferricyanide complex formation is not expected to occur
How should this work, how can Fe 2+ reduce Fe 3+

Where do you read it, that Fe 2+ is necessary.
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