Final answer:
The 'stickiness' of water is due to cohesion, where hydrogen bonds make water molecules stick together, resulting in high surface tension. These properties enable water droplets to form and insects to walk on water surfaces, and are crucial for biological processes, including the upward movement of water in plants and temperature regulation in humans.
Step-by-step explanation:
Understanding Water's Cohesive Nature
The stickiness of water molecules is a remarkable phenomenon arising from the molecule's unique structure and interactions. At the heart of this property is cohesion, which is the ability of water molecules to stick together, primarily due to hydrogen bonds that form between the oxygen of one water molecule and the hydrogen of another. This cohesive force is why water tends to form droplets on surfaces and is also responsible for the high degree of surface tension that water exhibits, allowing insects to walk on its surface, and a sewing needle to float when placed gently on water.
Furthermore, cohesion plays a significant role in biological processes such as capillary action, which allows water to move up the stems of plants. In contrast, adhesion refers to the attraction between water molecules and the molecules of other materials, which also contributes to capillary action. Water's cohesive and adhesive properties are vital for sustaining life, influencing everything from plant nutrition to the regulation of body temperature in humans through sweat and the heat of vaporization.