Question Detail
Question
If the cohesive forces within a liquid are greater than the adhesive forces between the liquid and its container, what is the range of the contact angle θ?
Correct Answer
Option C is the correct answer.
Detailed Explanation
When cohesive forces dominate, the liquid molecules are more strongly attracted to each other than to the container wall. The liquid pulls away from the wall, forming a convex meniscus, resulting in a contact angle θ that is greater than 90°, up to 180°.
Hint
Stronger attraction within the liquid (cohesion) than to the wall (adhesion) causes the liquid to avoid the wall, creating a large contact angle.