Answer:
+ 3.87 V
Explanation:
Data provided in the question:
The galvanic (voltaic) cell is composed of 1.0 M magnesium ion solution and 1.0 M gold(III) ion solution
Now,
The standard potential for this cell at 25°C ,
E₀ = [tex]E_{\textup{Anode}}-E_{\textup{Cathode}}[/tex]
i.e
E₀ = [tex]E_{Au^{3+}/Au}-E_{\textup{Mg^{2+}/Mg}}[/tex]
also,
from the standard reduction potential table
Mg²⁺ (aq) + 2e⁻ ⇒ Mg (s) E = -2.71 V
Au³⁺ (aq) + 3 e⁻ ⇒ Au (s) E = +1.50 V
Therefore,
E₀ = 1.50 - ( -2.37 )
or
E₀ = + 3.87 V
