Charcoal is activated

Options

A. by cooling it from `143^(@)` K to `127^(@)` C in vacuum
B. by cooling it to 23 K in vacuum
C. by heating it from 573 K to 1273 in vacuum
D. by heating upto 300 K

Answer

To solve the question regarding the activation of charcoal, we need to understand the process of activation and the conditions under which charcoal becomes activated.

### Step-by-Step Solution:

1. **Understanding Activated Charcoal**:
Activated charcoal is a form of carbon that has been processed to have small, low-volume pores that increase the surface area available for adsorption or chemical reactions. This process enhances its adsorptive power.

2. **Conditions for Activation**:
The activation of charcoal typically involves heating it to high temperatures. The range for activation is generally between 300 degrees Celsius to 1000 degrees Celsius, which corresponds to approximately 573 Kelvin to 1273 Kelvin.

3. **Analyzing the Options**:
- **Option A**: Cooling from 143°C to 127°C in vacuum. This does not activate charcoal; instead, it would reduce its temperature.
- **Option B**: Cooling to 23 Kelvin in vacuum. This is an extremely low temperature and would not activate charcoal.
- **Option C**: Heating from 573 Kelvin to 1273 Kelvin in vacuum. This falls within the activation temperature range and is a valid method for activating charcoal.
- **Option D**: Heating up to 300 Kelvin. This is too low to activate charcoal.

4. **Conclusion**:
The correct option for the activation of charcoal is **Option C**: by heating it from 573 Kelvin to 1273 Kelvin in vacuum.

### Final Answer:
C option is correct: by heating it from 573 Kelvin to 1273 Kelvin in vacuum.