[ajax0604]

I am doing a multiple choice question which asks which equation best describes the overall redox reaction occurring in the electrolysis of 1.0M tin(IV) chloride.
I have narrowed it down to these two:
Sn⁴⁺(aq) + 2H₂O(l) --> Sn(s) +O₂(g) + 4H⁺(aq)
Sn⁴⁺ (aq)+ 2Cl^-(aq) --> Sn(s) +Cl₂(g)
I first thought it was the first equation but since the concentration of Cl^- ions will be 4.0M, would they preferentially oxidise instead of water?

[Borek]

Have you tried to consult the standard reduction potential table?

[ajax0604]

Yes. The table shows that water is a better reductant but since the concentration of chloride will be considerably higher than the 1.0M  as per standard conditions, I think it may preferentially react.

[Borek]

This is tricky. You are not told what the pH is, plus oxygen evolution is heavily influenced by the kinetics (it is pretty slow thus requires huge overpotentials).

I have no idea what answer they expect. From what I remember during simple electrolysis of NaCl both gases - O₂ and Cl₂ - are produced.

[ajax0604]

The question mentions that 1.50A is applied for 15 minutes but nothing about voltage and pH

[Enthalpy]

Are the charges balanced in every equation? This eliminates some answers.

[ajax0604]

Thanks! I didn't see that