Question

Given below are two statements:
Statement I: Viscosity of liquid decreases with an increase in temperature.
Statement II: The units of viscosity are kg m^-1 s^-2.

• A. Both Statement I and Statement II are correct
• B. Both Statement I and Statement II are not correct
• C. Statement I is correct, but Statement II is not correct
• D. Statement I is not correct, but Statement II is correct

Hint:

- Viscosity of liquids decreases with increasing temperature.
 

Answer 1

The Correct Option is C

Step 1: Understanding viscosity behavior
- Viscosity is a measure of a fluid’s resistance to flow.
- As temperature increases, the intermolecular forces weaken, decreasing viscosity.
- This applies to liquids, whereas for gases, viscosity increases with temperature due to molecular kinetic energy increase.

Step 2: Understanding viscosity units
- The SI unit of viscosity is the Pascal-second (Pa·s), which is equivalent to N·s/m²
- This can be written as: Pa·s = kg/m·s
- The given unit (kg m^-1 s^-2) is incorrect for viscosity but correct for pressure.