Water does not wet an oily glass because

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(D) The wetting of a surface by a liquid depends on the relative magnitudes of cohesive and adhesive forces.Cohesive forces are the forces of attracti

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Cohesive force of water $>$ adhesive force between water and oil molecules

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(D) The wetting of a surface by a liquid depends on the relative magnitudes of cohesive and adhesive forces.Cohesive forces are the forces of attraction between molecules of the same substance,while adhesive forces are the forces of attraction between molecules of different substances.For water to wet a surface,the adhesive force between water molecules and the surface molecules must be greater than the cohesive force between water molecules.In the case of an oily glass,the adhesive force between water molecules and the oil-coated glass surface is significantly weaker than the cohesive force between the water molecules themselves.Therefore,the water molecules prefer to stay together rather than spread over the oily surface,preventing wetting.Thus,the correct condition is: Cohesive force of water $>$ adhesive force between water and oil molecules.

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