The number of incorrect statement/s from the following is/are
(1) Water vapours are adsorbed by anhydrous calcium chloride.
(2) There is a decrease in surface energy during adsorption.
(3) As the adsorption proceeds, `Delta H` becomes more and more negative.
(4) Adsorption is accompanied by decrease in entropy of the system.

Answer

To determine the number of incorrect statements from the provided options, let's analyze each statement one by one.

**Step 1: Analyze Statement 1**
- Statement: "Water vapours are adsorbed by anhydrous calcium chloride."
- Analysis: This statement is **incorrect**. Anhydrous calcium chloride is a desiccant that absorbs water vapors, not adsorbs them. The correct term is "absorbed," not "adsorbed."

**Step 2: Analyze Statement 2**
- Statement: "There is a decrease in surface energy during adsorption."
- Analysis: This statement is **correct**. During adsorption, molecules adhere to a surface, leading to a decrease in surface energy as the system becomes more stable.

**Step 3: Analyze Statement 3**
- Statement: "As the adsorption proceeds, ΔH becomes more and more negative."
- Analysis: This statement is **incorrect**. As adsorption occurs, the enthalpy change (ΔH) becomes less negative (or more positive) because the available sites for adsorption decrease, leading to a decrease in the energy released.

**Step 4: Analyze Statement 4**
- Statement: "Adsorption is accompanied by a decrease in entropy of the system."
- Analysis: This statement is **correct**. When molecules adsorb onto a surface, the randomness (or disorder) of the system decreases, leading to a decrease in entropy.

**Conclusion:**
- Incorrect statements: Statement 1 and Statement 3.
- Total number of incorrect statements: **2**

### Final Answer:
The number of incorrect statements is **2**.

---