The angle of contact at the interface of water-glass is 0o, ethyl alcohol-glass is 0o, mercury-glass is 140o, and methyl iodide-glass is 30o. A glass capillary is put in a trough containing one of these four liquids. It is observed that the meniscus is convex. The liquid in the trough is a) water b) ethyl alcohol c) mercury d) methyl iodide
Correct option is C) The meniscus of liquid in a capillary tube will be convex upwards if the angle of contact is obtuse. It is so when one end of a glass capillary tube is immersed in a trough of mercury.
