Question

A concentration cell consists of two Sn/Sn2+ half-cells. The electrolyte in compartment A is 0.10 M Sn(NO3)2. The electrolyte in B is 0.87 M Sn(NO3)2. Which half-cell houses the cathode? What is the voltage of the cell? Cathode: half-cell A half-cell B Voltage of cell: V

Answer 1

Answer:

In compartment A, the solution will be concentrated with respect to compartment B, however, over time both compartments will have the same concentration. In compartment B it houses the cathode.

the voltage of the cell is 0.0315 V

Explanation:

Given:

Electrolyte in compartment A is 0.10 M

Electrolyte in compartment B is 0.87 M

Questions:

Which half-cell houses the cathode?

What is the voltage of the cell, V = ?

In both compartments, the reactions are:

A: Sn → Sn²⁺ + 2e⁻

B: Sn²⁺ + 2e⁻ → Sn

In compartment A, the solution will be concentrated with respect to compartment B, however, over time both compartments will have the same concentration. In compartment B it houses the cathode.

The voltage of the cell

$V=E_{in} -\frac{0.0592}{nlog(C_{A} /C_{B} )}$

Here

n = 2 due the two electrons transferred

Ein = 0

Substituting values:

$V=0-\frac{0.0592}{2*log(0.1/0.87)} =0.0315V$