To find the standard potential of `M^(3+)//M` electrode , the following cell is constituted : `Pt|M|M^(3+((.001moLL^(-1)|| Ag ^(+) ((0.01moLL^(-1))|` Ag. The emf of the cell is found to be 0.421 volt at 298 K. The standard potential of half reaction `M^(3+)+ 3e^(-) to M` at 298 K will be :
(Given `E_(Ag^(+)//Ag^(@)` at 298 K = 0.80 Volt)

Options

A. (0.32Volt)
B. (0.66Volt)
C. (0.38VOlt)
D. (1.28Volt)

Explanation

To find the standard potential of the half-reaction \( M^{3+} + 3e^- \rightarrow M \), we can follow these steps:

### Step 1: Write the cell notation and identify components
The cell notation given is:
\[ \text{Pt} | M | M^{3+} (0.001 \, \text{mol/L}) || \text{Ag}^+ (0.01 \, \text{mol/L}) | \text{Ag} \]

Here, the left side represents the anode (where oxidation occurs) and the right side represents the cathode (where reduction occurs).

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