Question

Which one of the following statements is ‘NOT’ true about the angle of contact of a liquid?

• A. Any increase in the temperature of the liquid does not decrease its angle of contact.
• B. Angle of contact depends upon the nature of liquid and solid in contact
• C. If an impurity is added in the liquid then it’s angle of contact changes.
• D. At a given temperature, the angle of contact is constant for a solid-liquid surface.

Answer 1

Answer: (D)

At a given temperature, the angle of contact is constant for a solid-liquid surface.

Answer 2

The angle of contact is not necessarily constant for a solid-liquid surface at a given temperature. It can vary depending on various factors such as the nature of the liquid and solid in contact, the presence of impurities, and the surface tension of the liquid.
So, the correct answer is (D) At a given temperature, the angle of contact is constant for a solid-liquid surface.