The value of Eºcell for the reaction Zn(s) + Cu2+(aq) <=> Zn2+(aq) + Cu(s) is 1.10 V. What is the value of E for a cell in which [Zn2+] = 1.0 x 10-3 M and [Cu2+] = 1.0 M?

Respuesta :

Answer: The cell potential of the above reaction is 1.2 V

Explanation:

The given chemical reaction follows:

[tex]Zn(s)+Cu^{2+}(aq.)\rightarrow Zn^{2+}(aq.)+Cu(s)[/tex]

Oxidation half reaction: [tex]Zn(s)\rightarrow Zn^{2+}+2e^-[/tex]

Reduction half reaction: [tex]Cu^{2+}+2e^-\rightarrow Cu(s)[/tex]

To calculate the EMF of the cell, we use the Nernst equation, which is:

[tex]E_{cell}=E^o_{cell}-\frac{0.059}{n}\log \frac{[Zn^{2+}]}{[Cu^{2+}]}[/tex]

where,

[tex]E_{cell}[/tex] = electrode potential of the cell = ? V

[tex]E^o_{cell}[/tex] = standard electrode potential of the cell = 1.1 V

n = number of electrons exchanged = 2

[tex][Cu^{2+}]=1.0M[/tex]

[tex][Zn^{2+}]=1.0\times 10^{-3}M[/tex]

Putting values in above equation, we get:

[tex]E_{cell}=1.1-\frac{0.059}{2}\times \log(\frac{1.0\times 10^{-3}}{1.0})\\\\E_{cell}=1.2V[/tex]

Hence, the cell potential of the above reaction is 1.2 V