posted by lholmq on .
Ok, I'm sure this is a stupid question, but when I try to break down the following equation to its net ionic equation, all of the elements cancel out. I'm obviously doing something wrong...
Can anyone help with the net ionic equation for:
Fe(NO3)3 (aq) + 3KSCN (aq) ---> Fe(SCN)3 (aq) + 3KNO3 (aq)
? Thank you.
Fe(NO3)3 + 3KSCN >> FeSCN(2+) + 3KNO3
But it's not broken down into ions. Isn't is supposed to be?
The net ionic equation is
The equation above is the molecular equation (but it isn't balanced because the SCN is not balanced). The net ionic equation is
Fe^+3 + SCN^- ==> FeSCN^+2
Sorry, I meant to mention that all the Fe in the equation is Fe3+ (maybe that's obvious from the equation...). In which equation is the SCN not balanced? Mine or Kara's? And how did you get to this answer? Thank you so much.
Everything is balanced in your equation but it's incorrect because it doesn't show the FeSCN^+2 ion. The SCN^- is not balanced in Kara's post.
How did I get my answer?
Ferric ion forms a complex ion with SCN and the formula of the complex is FeSCN^+2. And we know that KNO3 is ionic so those ions would cancel. Therefore, the only ions that react are ferric ion and SCN ion. It's a qualitative test for either SCN^- or iron(III) and it's very sensitive. The complex is a blood red color and is visible to the eye at extremely low concentrations. In fact, it is so sensitive that the reaction is used as an indicator in some quantitative titrations. I hope this helps.
Yes, it helps a lot. Thanks so much! :)
What would the balanced chemical equation be?