Concept:Viscosity is a liquid's resistance to flow, caused by intermolecular forces holding sliding molecular layers together. Adding thermal energy disrupts these forces.
Formula:$$ \text{Viscosity} \propto \frac{1}{\text{Temperature}} $$
Solution:- As Temperature increases, the average kinetic energy of the liquid molecules rises significantly.
- This energetic, rapid motion overcomes and breaks apart the intermolecular forces (like hydrogen bonds) holding the fluid layers together.
- With weaker attractive holds between the sliding layers, the "internal friction" plummets, causing the viscosity to visibly decrease (the liquid flows much more easily).
Why other options are incorrect:Increases in Molecular mass and Intermolecular forces generally
increase viscosity. Atmospheric pressure changes have a negligible effect on the viscosity of virtually incompressible liquids.
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