Question

What is the formula for iron(III) cyanide ?

Answer 1

`Fe(CN)_3`

Explanation:

Iron(III) cyanide means that iron exists as a ferric compound, i.e. it is in its trivalent state, or existing as `Fe^(3+)`.

Cyanide `(CN^-)` has a `-1` charge, so to make the molecule neutral, we need `3` cyanide molecules to balance iron's `+3` charge.

So, the formula for iron(III) cyanide or ferric cyanide is

`Fe(CN)_3`

Answer 2

• It might be `"Fe"("CN")_3`

• . Because iron , according to the question, has a valency of `color(red)(+3`.

• We again know that the valency of `"CN"^-` is `color(red)(-1`.

Let's, there will be `color(red)(x" "`number of `"Fe"^(3+)` and `color(red)(y" "`number of `"CN"^-` ion.

We know that the charge of a compound will be zero, then we can write,

`(+3)xx x+(-1)xxy=0`

`=>3x=y`

`=>x:y=1:3`

Hope it helps...
Thank you..