Give proper reason for the followings. i) Evaporation takes place from the surface of liquid. [1] ii) Liquid drops are spherical shape. [1]

i) Evaporation takes place from the surface of liquid Evaporation is a surface phenomenon because it requires sufficient kinetic energy for molecules to escape the liquid phase. Molecules in the bulk of the liquid are surrounded by other molecules and experience intermolecular forces (e.g., hydrogen bonding, van der Waals forces) that restrict their movement. Only molecules at the surface have enough energy to overcome these forces and escape into the gaseous phase. Additionally, the surface area of a liquid provides the maximum exposure to atmospheric pressure and temperature fluctuations, facilitating the transition from liquid to vapor.

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ii) Liquid drops are spherical in shape Liquid drops adopt a spherical shape due to surface tension, which is a property arising from cohesive forces between liquid molecules. These forces minimize the surface area for a given volume, and a sphere is the geometric shape with the minimum surface area-to-volume ratio. Gravity and external forces (e.g., adhesion to a surface) can distort this shape, but in the absence of such forces, the drop remains spherical. This principle is governed by the Laplace pressure, where the internal pressure balances the surface tension to maintain equilibrium.