Chapter 19, Problem 19.119QP

Interpretation Introduction

Interpretation:

Even though ${\text{Sn}}^{\text{2+}}\text{/}\text{Sn}\text{and}{\text{Cr}}^{\text{3+}}\text{/}\text{Cr}$ have different standard reduction potential, A galvanic cell can be constructed using Fe electrode in $\text{Fe}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}$ solution; the reason has to be explained.

Concept introduction:

Conventional notation for representing Galvanic cell:

The single vertical line represents a phase boundary. The double vertical line denotes the salt bridge. Anode is written first to the left of the double lines, and the cathode is written to the right of the double lines. The electron is moving from Anode to cathode. At anode oxidation process occurs and at cathode reduction process occurs.

Standard reduction potential: The voltage associated with a reduction reaction at an electrode when all solutes are 1M and all gases are at 1 atm. The hydrogen electrode is called the standard hydrogen electrode (SHE).

Standard emf: ${\text{E}}_{cell}^0$ is composed of a contribution from the anode and a contribution from the cathode is given by,

$E_{cell}^o=E_{cathode}^o-E_{anode}^o$

Where both $E_{cathode}^o$ and $E_{anode}^o$ are the standard reduction potentials of the electrodes.