Adsorption is a phenomenon of surface attraction, which causes molecules of one substance...
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Adsorption is a phenomenon of surface attraction, which causes molecules of one substance to adhere to the surface of another. What is this surface attraction force called?
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Adsorption occurs when molecules of a gas or liquid adhere to the surface of a solid or liquid. This attraction between molecules of different substances is defined as adhesion, whereas attraction between similar molecules is called cohesion.
Step-by-step Derivation:
Step 1: Analyze the definition of adsorption. Adsorption is the accumulation of molecules of a substance (adsorbate) on the surface of another substance (adsorbent).
Step 2: Identify the nature of the force involved. Since the process involves two different substances (the surface and the incoming molecules), the force is an intermolecular attraction between unlike molecules.
Step 3: Compare with the provided options:
- Adhesion: The attraction between molecules of different substances. (Matches the definition of adsorption surface force).
- Cohesion: The attraction between molecules of the same substance.
- Attraction: A general term, not a specific scientific name for this surface force.
- Affinity: A general chemical tendency for two substances to react or bond, but not the specific physical force of surface adherence.
Step 4: Conclusion: The specific force causing molecules to adhere to a surface of another substance is Adhesion.