Which of the following statements is/are correct ?

Options

A. Physical adsorption is multilayer, non-directional, and non-specific.
B. On some cases, solvent may be adsorbed in preference to the solute on the surface of the adsorbent.
C. Chemical adsorption increases with increases in temperature.
D. Due to adsorption, surface energy increases.

Explanation

To determine which statements regarding adsorption are correct, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Analyzing Option 1**:
- The statement claims that "physical adsorption is multilayer, non-directional, and non-specific."
- **Explanation**: Physical adsorption involves weak Van der Waals forces, which allow multiple layers of adsorbate to form on the adsorbent. This type of adsorption is indeed non-directional and non-specific because the weak forces do not favor any particular orientation or specific type of adsorbate.
- **Conclusion**: This statement is **correct**.

2. **Analyzing Option 2**:
- The statement claims that "in some cases, solvent may be adsorbed in preference to the solute on the surface of the adsorbent."
- **Explanation**: In adsorption processes, it is typically the solute that gets adsorbed onto the surface of the adsorbent, not the solvent. The statement suggests a reversal of this process, which is not supported by the principles of adsorption.
- **Conclusion**: This statement is **incorrect**.

3. **Analyzing Option 3**:
- The statement claims that "chemical adsorption increases with an increase in temperature."
- **Explanation**: Chemical adsorption typically involves stronger interactions (chemical bonds) and can increase with temperature, as higher temperatures can provide the necessary energy to overcome activation barriers for the chemical reactions involved in adsorption.
- **Conclusion**: This statement is **correct**.

4. **Analyzing Option 4**:
- The statement claims that "due to adsorption, surface energy increases."
- **Explanation**: When adsorption occurs, the surface energy actually decreases because the adsorbate molecules occupy surface sites, thus reducing the available surface area for further adsorption and lowering the overall surface energy.
- **Conclusion**: This statement is **incorrect**.

### Final Answer:
The correct statements are:
- **Option 1**: Correct
- **Option 3**: Correct