Physics
Describe the molecular model for a liquid. How does it explain that a liquid has no definite shape, but has a definite volume ?
Answer
Features of molecular model for a liquid are :
- The molecules in a liquid are loosely packed due to weaker attractive forces than in solids. They can move over each other, within the boundary of the liquid, so a liquid has a definite volume but no definite shape.
- The inter-molecular space in a liquid is greater than that in a solid, so they generally have low density as compared to a solid, i.e., they are more compressible.
- The motion of molecules in a liquid is irregular and random within the boundary of the liquid.
Thus, this model concludes that liquids do not have a definite shape, but have a definite volume and can flow from a higher to a lower level. They show the property of viscosity and surface tension because of the cohesive forces.
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