Explain why water in a narrow glass tube has a concave meniscus while mecury in the same tube, has a convex meniscus
Explanation
For water in a glass tube, the forces of adhesion between the water and glass molecules are greater than the force of cohesion between the water molecules hence water clings to glass forming a concave meniscus. On the other hand, the forces of cohesion between mercury molecules are greater than those between mercury molecules and glass molecules, so mercury molecules cling to each other forming convex meniscus.