Which one of the following is an adsorbent?

Options

A. lamp black
B. methane
C. coal
D. charcoal

Answer

To determine which one of the following is an adsorbent, we need to understand what an adsorbent is and identify examples of adsorbents.

### Step-by-Step Solution:

1. **Define Adsorbent**: An adsorbent is a substance that has the ability to attract and hold particles (adsorbate) on its surface. This process is called adsorption.

**Hint**: Remember that adsorption is different from absorption. Adsorption involves the accumulation of molecules on the surface, while absorption involves the incorporation of molecules into a bulk material.

2. **Identify Common Adsorbents**: Some common examples of adsorbents include activated carbon, silica gel, and activated alumina. These materials have a high surface area and are effective at trapping other substances.

**Hint**: Think of materials that are used in filters or to purify substances; they often act as adsorbents.

3. **Consider the Given Options**: If the question provides a list of substances, look for those known for their adsorptive properties. For instance, activated carbon, charcoal, and silica gel are well-known adsorbents.

**Hint**: If you see "activated carbon" or "charcoal" in the options, they are likely candidates for being adsorbents.

4. **Conclusion**: Among the options, charcoal is identified as an effective adsorbent. It is a form of carbon that has a large surface area, making it suitable for trapping various substances.

**Hint**: Charcoal is often used in air and water purification systems due to its adsorptive capabilities.

### Final Answer:
Charcoal is an adsorbent.