The standard electrode potentials of Zn, Ag and Cu are -0.76, 0.80 and 0.34 volt respectively, then:

Options

A. Ag can oxidised Zn and Cu
B. Ag can reduce `Zn^(2+)` and `Cu^(2+)`
C. Zn can reduce `Ag^(+)` and `Cu^(2+)`
D. Cu can oxidise Zn and Ag

Answer

To solve the question regarding the standard electrode potentials of Zn, Ag, and Cu, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Standard Electrode Potentials**:
- The standard electrode potentials given are:
- Zn²⁺/Zn: -0.76 V
- Ag⁺/Ag: +0.80 V
- Cu²⁺/Cu: +0.34 V

2. **Understand the Meaning of Standard Electrode Potentials**:
- The standard electrode potential indicates the tendency of a species to be reduced. A higher (more positive) value means a stronger oxidizing agent, while a lower (more negative) value indicates a stronger reducing agent.

3. **Determine the Reducing and Oxidizing Agents**:
- **Reducing Agent**: The species with the lowest standard reduction potential (most negative) is the best reducing agent. Here, Zn (-0.76 V) is the best reducing agent.
- **Oxidizing Agents**: The species with the highest standard reduction potential (most positive) is the best oxidizing agent. Here, Ag (+0.80 V) is the best oxidizing agent.

4. **Write the Half-Reactions**:
- For Zn:
\[ \text{Zn} \rightarrow \text{Zn}^{2+} + 2e^- \quad (\text{oxidation}) \]
- For Ag:
\[ \text{Ag}^+ + e^- \rightarrow \text{Ag} \quad (\text{reduction}) \]
- For Cu:
\[ \text{Cu}^{2+} + 2e^- \rightarrow \text{Cu} \quad (\text{reduction}) \]

5. **Determine Which Reactions Occur**:
- Since Zn is a strong reducing agent, it can reduce both Ag⁺ and Cu²⁺. Therefore, Zn will oxidize itself while reducing Ag⁺ to Ag and Cu²⁺ to Cu.

6. **Conclusion**:
- Based on the standard electrode potentials, the correct conclusion is that Zinc will reduce both Silver ions (Ag⁺) and Copper ions (Cu²⁺). Therefore, the correct answer is option C: Zinc reduces Ag⁺ and Cu²⁺.

### Final Answer:
The correct answer is **C**: Zinc reduces Ag⁺ and Cu²⁺.