The emf of the cell involving the following reaction, `2Ag^(+) +H_(2) rarr 2Ag +2H^(+)` is `0.80` volt. The standard oxidation potential of silver electrode is:-

Options

A. `-0.80` volt
B. `0.80` volt
C. `0.40` volt
D. `-0.40` volt

Explanation

To find the standard oxidation potential of the silver electrode from the given cell reaction, we will follow these steps:

### Step 1: Understand the Cell Reaction
The cell reaction given is:
\[ 2Ag^+ + H_2 \rightarrow 2Ag + 2H^+ \]

In this reaction, silver ions (\(Ag^+\)) are being reduced to silver metal (\(Ag\)), while hydrogen gas (\(H_2\)) is being oxidized to hydrogen ions (\(H^+\)).

### Step 2: Identify the Oxidation and Reduction Processes
- **Reduction**: \(Ag^+ + e^- \rightarrow Ag\) (Silver is reduced)
- **Oxidation**: \(H_2 \rightarrow 2H^+ + 2e^-\) (Hydrogen is oxidized)

### Step 3: Determine the Standard Reduction Potentials
The standard reduction potential for the hydrogen electrode is defined as:
\[ E^\circ_{H^+/H_2} = 0 \, \text{V} \]

Let \(E^\circ_{Ag^+/Ag}\) be the standard reduction potential for the silver electrode.

### Step 4: Use the EMF of the Cell
The EMF of the cell is given as:
\[ E^\circ_{cell} = E^\circ_{cathode} - E^\circ_{anode} \]

In this case:
- The cathode is where reduction occurs (silver electrode).
- The anode is where oxidation occurs (hydrogen electrode).

Thus, we can write:
\[ E^\circ_{cell} = E^\circ_{Ag} - E^\circ_{H_2} \]

Substituting the known values:
\[ 0.80 \, \text{V} = E^\circ_{Ag} - 0 \]

### Step 5: Solve for the Standard Reduction Potential of Silver
From the equation:
\[ E^\circ_{Ag} = 0.80 \, \text{V} \]

### Step 6: Find the Standard Oxidation Potential
The standard oxidation potential is the negative of the standard reduction potential:
\[ E^\circ_{oxidation} = -E^\circ_{Ag} \]
\[ E^\circ_{oxidation} = -0.80 \, \text{V} \]

### Conclusion
The standard oxidation potential of the silver electrode is:
\[ \text{Standard Oxidation Potential} = -0.80 \, \text{V} \]

### Final Answer
The correct option is **Option A: -0.80 V**.

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