Which statement is incorrect for chemisorption?

Options

A. It is an exothermic process
B. It increases with increase in surface area
C. It is highly specific
D. It is recersible in nature

Answer

To determine which statement is incorrect regarding chemisorption, we need to analyze the characteristics of chemisorption and evaluate the provided options. Here’s a step-by-step solution:

### Step 1: Understand Chemisorption
Chemisorption is the process where atoms, ions, or molecules from a gas, liquid, or dissolved solid adhere to a surface through the formation of strong chemical bonds. This process is characterized by the following features:
- It involves the formation of a chemical bond between the adsorbate (the substance being adsorbed) and the adsorbent (the surface).
- It is typically an exothermic process, meaning it releases heat.

**Hint:** Remember that chemisorption involves strong chemical bonds, which distinguishes it from physisorption.

### Step 2: Analyze Each Statement
Now, let's evaluate the statements provided in the question:

1. **Statement 1:** Chemisorption is an exothermic process.
- This statement is **correct** because energy is released when chemical bonds are formed during chemisorption.

2. **Statement 2:** Chemisorption increases with an increase in surface area.
- This statement is also **correct**. A larger surface area allows for more active sites for the adsorbate to form chemical bonds, thus increasing the extent of chemisorption.

3. **Statement 3:** Chemisorption is highly specific.
- This statement is **correct** as well. Chemisorption occurs only if there is a suitable chemical interaction between the adsorbate and adsorbent, making it specific to certain pairs of substances.

4. **Statement 4:** Chemisorption is reversible in nature.
- This statement is **incorrect**. Chemisorption is generally considered irreversible because the strong chemical bonds formed during the process are not easily broken. Once the adsorbate is bonded to the adsorbent, it typically cannot be removed without significant energy input.

### Conclusion
The incorrect statement regarding chemisorption is **Statement 4**, which claims that chemisorption is reversible in nature.

### Final Answer
The incorrect statement for chemisorption is: **It is reversible in nature.**

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