The increase of temperature results in

Viscosity is a measure of a fluid's resistance to flow. It is affected by temperature differently for liquids and gases.

Effect of Temperature on Liquids:

- As temperature increases, the kinetic energy of liquid molecules increases.

This weakens intermolecular forces, making it easier for the liquid to flow.
As a result, the viscosity of a liquid decreases with an increase in temperature.


Effect of Temperature on Gases:

- In gases, viscosity is primarily due to the momentum transfer between molecules.

As temperature increases, the molecular collisions increase, leading to higher viscosity.

Analysis of Options:

- Option A: Increase in viscosity of gas → Correct for gases, but the question focuses on general fluid behavior.

Option B: Increase in viscosity of liquid → Incorrect, as liquid viscosity decreases with temperature.
Option C: Decrease in viscosity of gas → Incorrect, as gas viscosity increases with temperature.
Option D: Decrease in viscosity of liquid → Correct, as liquid viscosity reduces when temperature rises.



Conclusion: The correct answer is Option D: decrease in viscosity of liquid because higher temperatures reduce intermolecular forces in liquids, allowing them to flow more easily.