Formation of Ti^3+ Ions in Reaction with Acidified Potassium Dichromate

[hobomoe]

Homework Statement

Acidified potassium dichromate is an oxidant. It will react with titanium metal which is oxidised to form titanium ions.

Show that Ti^3+ and not Ti^2+ is formed in the reaction. Your answer should include chemical equations for any possible reactions and justification for you conclusion based of E values.

E(Cr207^2-/Cr^3+)=+1.33v E(Ti^2+/Ti)=-1.63v E(Ti^3+/Ti^2+)=-2.32v

Homework Equations

E(Cr207^2-/Cr^3+)=+1.33v E(Ti^2+/Ti)=-1.63v E(Ti^3+/Ti^2+)=-2.32v

The Attempt at a Solution

E(Cr207^2-/Cr^3+)-E(Ti^2+/Ti)=2.96v
E(Cr207^2-/Cr^3+)-E(Ti^3+/Ti^2+)=3.65v
Dichromate ions react with the titanium metal to form Ti^2+ ions. These ions then react with remaining dichromate ions to form Ti^3+ ions. It will try to form Ti^3+ ions from the Ti^2+ ions in order to get a greater E value.

 

[hobomoe]

zzz so many views and no answer

 

[Borek]

E(Ti^3+/Ti^2+)=-2.32v

And not -0.37V?

What I don't like about the question is that pH is not given. Or at least it should state standard conditions.

 

[hobomoe]

Acidified potassium dichromate, so its acidic. Don't need to go super indepth, it's only final high school year redox.