Question

Why does surface tension and viscosity decrease with temperature?

Answer 1

surface tension and viscosity result due to the inmolecular attractions or more simply vander waal's forces.when temperature of a body is raised the particles of the body start gaining more kinetic energy that is they start moving more vigorously.since the volume of any body increases on heating therefore the intermolecular attractions become more and more less resulting in decrease of surface tension and viscosity which are due to attraction of a molecule by its neighboring molecules or bottom molecules as in the case of surface tension.the summary is that more the kinetic energy of a body,more is the motion of particles and the faster the particles move the lesser is the intermolecular attractions........
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