AP BIOLOGY

Detailed explanation-1: -Water molecules are attracted to the molecules in the wall of the glass beaker. And since water molecules like to stick together, when the molecules touching the glass cling to it, other water molecules cling to the molecules touching the glass, forming the meniscus.

Detailed explanation-2: -Water Is Cohesive This water can stay above the glass because of the property of cohesion. In cohesion, water molecules are attracted to each other (because of hydrogen bonding), keeping the molecules together at the liquid-air (gas) interface, although there is no more room in the glass.

Detailed explanation-3: -Water molecules are not attracted only to each other. Adhesion is the tendency of water to stick to other substances. You see adhesion at work when you add water to a graduated cylinder. At the surface, water creeps up slightly at the sides of the cylinder, forming a curved surface called a meniscus.

Detailed explanation-4: -Glass molecules also happen to be polar. Again, since polar molecules like to stick together, the water in a glass tube will actually tend to stick to the sides of the tube! You can see this at the top of the graduated cylinder, where the water will slightly creep up the sides and form a curve, which is the meniscus.

Detailed explanation-5: -Adhesion makes a water drop a drop. Water is highly cohesive-it is the highest of the non-metallic liquids. Water is sticky and clumps together into drops because of its cohesive properties, but chemistry and electricity are involved at a more detailed level to make this possible.