Question

1. why do water molecules at the surface of a pond have elastic - like properties, forming what we call surface tension?

Explanation:

Water molecules are polar and have hydrogen - bonding. Molecules in the bulk have neighbors on all sides, but surface molecules have fewer neighbors above them. They are pulled more strongly inward by the molecules below and to the sides, creating a net inward force that gives the surface elastic - like properties.

Answer:

Water molecules are polar and hydrogen - bond. Surface molecules have a net inward pull due to fewer neighbors above, creating surface tension.