Two identical glass capillaries are dipped in water and mercury respectively. Predict the meniscus shape and whether the liquid rises or falls in each. Step 1: Water–glass: adhesion > cohesion, contact angle ≈ 0° (acute). The meniscus is concave (curves up at the walls), and water rises in the capillary. Step 2: Mercury–glass: cohesion > adhesion, contact angle ≈ 140° (obtuse). The meniscus is convex (dips down at the walls), and mercury is depressed below the outside level. Answer: Water: concave meniscus, capillary rise. Mercury: convex meniscus, capillary depression. The contact angle alone predicts both.