Question

Viscosity of gases _______with temperature, whereas viscosity of liquids _______with temperature.

• A. increases
• B. decreases

Answer 1

The viscosity of Gases:

1. The viscosity of a fluid (liquid or gas) is its resistance to a change in shape or movement of neighboring portions relative to one another.
2. Viscosity denotes resistance to flow.
3. Viscosity in gases is caused by molecules passing through layers of flow and transferring momentum between them.
4. This momentum transfer can be thought of as a frictional force between layers of flow.
5. Gas viscosity increases with temperature, whereas liquid viscosity decreases with temperature. Because intermolecular forces weaken with temperature, viscosity decreases.
6. Temperature increases typically cause an increase in molecular interchange because molecules move faster at higher temperatures. The coefficient of viscosity is a measure of the fluid's resistance to flow.