Why does a liquid tend to reduce its free surface area?

The sum of the forces of attraction acting on the molecules on the surface of the liquid, from the side of the molecules of the liquid, exceeds in absolute value. The sum of the forces of attraction acting on the part of air molecules. Therefore, the sum of all these forces is directed into the liquid.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.