Determine Eo for the following reaction, using the given standard reduction potentials

Question

Determine E^o for the following reaction, using the given standard reduction potentials:

Fe³⁺(aq) + Ti(s) → Fe²⁺(aq) + Ti²⁺(aq)

E^o for Ti²⁺(aq) = -1.63 V

E^o for Fe³⁺(aq) = 0.77 V

My answer is -2.4 but the correct answer is 2.4

Why is the answer positive?

Answer 1

Reduction takes place at the cathode

Oxidation takes place at the anode

Using reduction potentials, the Eº for the cell is reduction potential at cathode - reduction potential at anode

Fe³⁺ + e- ==> Fe²⁺ ... reduction (cathode) Eº = 0.77 V

Ti (s) ======> Ti²⁺ ...oxidation (anode) Eº = -1.63 V

Eº = cathode - anode = 0.77 - (-1.63) = 0.77 + 1.63

Eº = +2.4 V