Conditions essential for imbibition is/are

Options

A. Water potential gradient between the liquid imbibed and the adsorbent
B. Affinity between the adsorbent and the imbibed liquid
C. Hydrophobic adsorbent
D. Both (1) and (2)

Answer

**Step-by-Step Solution:**

1. **Understanding Imbibition:**
- Imbibition is the process where water is absorbed by a solid or gel, causing it to swell. This occurs due to the movement of water from an area of higher concentration to an area of lower concentration.

2. **Conditions for Imbibition:**
- There are two essential conditions for imbibition to occur:
- **Water Potential Gradient:** There must be a gradient in water potential between the surface of the adsorbent (the material absorbing water) and the imbibed liquid (the water being absorbed). This means that the water potential should be higher in the liquid than in the adsorbent.
- **Affinity Between Adsorbent and Liquid:** There should be an attraction or affinity between the adsorbent and the liquid being imbibed. This attraction helps facilitate the absorption process.

3. **Analyzing the Options:**
- Option 1 states that there is a water potential gradient between the liquid imbibed and the adsorbent. This is correct based on our understanding of imbibition.
- Option 2 mentions the affinity between the adsorbent and the imbibed liquid. This is also correct as it is one of the necessary conditions for imbibition.
- Option 4 states that both conditions (1 and 2) are correct.

4. **Conclusion:**
- Since both conditions are necessary for imbibition, the correct answer is option 4, which states that both conditions are essential.

**Final Answer:**
The conditions essential for imbibition are:
1. Water potential gradient between the liquid imbibed and the adsorbent.
2. Affinity between the adsorbent and the imbibed liquid.
Thus, the correct answer is option 4: Both 1 and 2 are correct.

---