Answer:
1. Polar 2. Hydrogen bonding 3. Cohesion 4. Surface tension
Explanation:
1. Water is a polar molecules due to the presence of unbalanced charges in its covalent bond.
2. This unbalanced charges causes the molecules to be polar and thus form hydrogen bonds with nearby molecules due to their opposite charges. The hydrogen atom carries the positive charge while the oxygen atom carries the negative charge. The opposing charges thus causes hydrogen and oxygen atoms in nearby molecules to be attracted to each other.
3. This attraction of the water molecules to each other is called cohesion. Cohesion is the force of attraction between similar molecules and this force of attraction is called a cohesive force.
4. Since the water molecules are attracted to each other due to a cohesive force, this cohesive force causes a thin film to form called surface tension. Thus, surface tension is the ability of the surface of a liquid to resist external forces due to cohesive forces in its molecules and thus form a thin film.
