The physical adsorption of gases on the solid surface is due to :

Options

A. vander Waals forces
B. covalent bonding
C. hydrogen bonding
D. All of these

Explanation

To solve the question regarding the physical adsorption of gases on a solid surface, we can break it down into the following steps:

### Step 1: Understand the concept of physical adsorption
Physical adsorption, also known as physisorption, is a process where gas molecules adhere to a solid surface through weak intermolecular forces.

### Step 2: Identify the forces involved in physical adsorption
The primary forces that govern physical adsorption are Van der Waals forces. These forces are weak and arise from temporary dipoles that occur when molecules are in close proximity to each other.

### Step 3: Differentiate between physical adsorption and chemical adsorption
It is important to distinguish between physical adsorption and chemical adsorption (chemisorption). Chemisorption involves the formation of strong chemical bonds (like covalent bonds) between the adsorbate and the surface, which is not the case in physical adsorption.

### Step 4: Analyze the options provided
Given the options A, B, C, and D, we need to determine which one correctly identifies the cause of physical adsorption. Since we established that physical adsorption is due to Van der Waals forces, we can conclude that the correct option must refer to these forces.

### Step 5: Conclude the answer
Based on our analysis, we can conclude that the physical adsorption of gases on solid surfaces is due to Van der Waals forces of attraction. Therefore, the correct answer is option A.

### Summary of the solution:
The physical adsorption of gases on solid surfaces is due to weak Van der Waals forces of attraction.

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