Activity 1G (Textbook) – Chemistry Form 5 Chapter 1 (Redox Equilibrium)

Activity 1G:
Carry out this activity collaboratively in groups.
1. Figure 1.19 shows an apparatus set-up for a voltaic cell.


(a) Based on Figure 1.19, and referring to the standard electrode potential of a half-cell:

(i) identify the negative and positive terminals.

(ii) write the cell notation for the voltaic cell.

(iii) write the half equations for oxidation reaction, reduction reaction and the overall ionic equation.

(iv) calculate the voltage of the cell.

Present your group’s results to your friends.


Answer:
(a)(i)
Negative terminal: Iron
Positive terminal : Silver

(a)(ii)
$$\mathrm{Fe}(\mathrm{s})\left|\mathrm{Fe}^{2+}(\mathrm{aq}) \| \mathrm{Ag}^{+}(\mathrm{aq})\right| \mathrm{Ag}(\mathrm{s})$$

(a)(iii)
$$\begin{aligned} \text { Oxidation half equation } & : \mathrm{Fe} \rightarrow \mathrm{Fe}^{2+}+2 \mathrm{e}^{-} \\ \text {Reduction half equation } & : \mathrm{Ag}^{+}+\mathrm{e}^{-} \rightarrow \mathrm{Ag} \\ \text { Overall ionic equation } & : \mathrm{Fe}+2 \mathrm{Ag}^{+} \rightarrow \mathrm{Fe}^{2+}+2 \mathrm{Ag} \end{aligned}$$

(a)(iv)
$$\mathrm{E}_{\text {cell }}^0=(+0.80)-(-0.44)=+1.24 \mathrm{~V}$$