Question

Consider the voltaic cellZn(s) + Cu{2+}(aq)--> Zn{2+}(aq)+Cu(s){}=chargeUnder standard conditions, what is the maximum electrical work, in Joules that can accomplish if 60 g of copper is plated out?

Answer 1

Answer:

Max. work done in 60 g of copper plated out is 200472.14 J

Explanation:

Given cell reaction is:

$Zn(s)+Cu^{2+} \rightarrow Zn^{2+}+Cu(s)$

Standard reduction potential of Zn electrode ($E_{Zn^{2+}/Zn}$) is 0.763 V.

Standard reduction potential of Cu electrode ($E_{Cu^{2+}/Cu}$) is -0.337 V.

Copper acts as cathode and Zinc acts as anode.

Cell potential (E) = E° cathode - E° anode

                           = 0.763 - (-0.337)

                           = 1.10 V

formula for the work done is as follows:

$W_{max}=-nFE$

Here, n is no. of electron involved in the reaction.

F(Faraday's constant) = 96500

In the given reaction, n = 2

$W_{max}=-nFE\\=-2 \times\ 96500 \times 1.10\\=-212300\ J/mol$

Therefore, 212300 J work is done by reducting 1 mol of copper.

Copper given is 60 g.

Molecular mass of copper is 63.54 g/mol.

$No.\ of\ mol = \frac{60\ g}{63.54\ g/mol}$

Max. work done in 60 g of copper plated out is:

$W_{max}=212300\ J/mol \times \frac{60\ g}{63.54\ g/mol} \\=200472.14\ J$