Which of the following is not correct

Options

A. Enthalpy of physical adsorption is less when compared to enthalpy of chemical adsorption
B. Milk is an example of emulsion
C. Physical adsorption increases with increase in temparature
D. Smoke is an aerosol

Answer

To determine which of the following statements is not correct, let's analyze each option step by step:

### Step 1: Analyze the First Statement
**Statement:** The enthalpy of physical adsorption is less when compared to the enthalpy of chemical adsorption.

**Explanation:**
- Physical adsorption involves weak van der Waals forces.
- Chemical adsorption involves strong chemical bonds.
- Since breaking weak bonds requires less energy, the enthalpy of physical adsorption is indeed less than that of chemical adsorption.

**Conclusion:** This statement is **correct**.

### Step 2: Analyze the Second Statement
**Statement:** Milk is an example of emulsion.

**Explanation:**
- An emulsion is a mixture where one liquid is dispersed in another.
- Milk consists of fat droplets dispersed in water, making it a classic example of an emulsion.

**Conclusion:** This statement is **correct**.

### Step 3: Analyze the Third Statement
**Statement:** Physical adsorption increases with increasing temperature.

**Explanation:**
- Adsorption is an exothermic process, meaning it releases heat.
- Increasing temperature typically decreases the extent of exothermic reactions, including adsorption.
- Therefore, physical adsorption does not increase with temperature; it actually decreases.

**Conclusion:** This statement is **not correct**.

### Step 4: Analyze the Fourth Statement
**Statement:** Smoke is an aerosol.

**Explanation:**
- An aerosol is a suspension of fine solid particles or liquid droplets in air.
- Smoke consists of tiny solid particles suspended in air, which fits the definition of an aerosol.

**Conclusion:** This statement is **correct**.

### Final Conclusion
The only statement that is not correct is the third one: "Physical adsorption increases with increasing temperature."

---