Standard reduction potential is calculated at

Options

A. `27^(@)C`
B. `25^(@)C`
C. `0^(@)C`
D. `100^(@)C`

Answer

To determine the temperature at which standard reduction potential is calculated, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Standard Reduction Potential**:
- Standard reduction potential is a measure of the tendency of a chemical species to be reduced, which means gaining electrons.

2. **Identify Standard Conditions**:
- Standard reduction potential is measured under specific conditions. These conditions include:
- Concentration of ions: 1 mole per decimeter cubed (1 M)
- Pressure: 1 atmosphere (atm)
- Temperature: This is what we need to determine.

3. **Recall the Standard Temperature**:
- The standard temperature for measuring standard reduction potentials is commonly accepted as 25 degrees Celsius.

4. **Conclusion**:
- Based on the definition and standard conditions, the temperature at which standard reduction potential is calculated is 25 degrees Celsius.

5. **Select the Correct Option**:
- Among the given options (27°C, 25°C, 0°C, 100°C), the correct answer is 25 degrees Celsius, which corresponds to option number 2.

### Final Answer:
- The standard reduction potential is calculated at **25 degrees Celsius**.

---