Question

What are the four emergent properties of water? Give an example of how each supports life.

1.

2.

3.

4.

Answer 1

1. The Cohesion of Water; The cohesion of water is the process of hydrogen bonding of water molecules to other water molecules. This property is essential in plants. The evaporation of water from the leaves of a tree, in effect, pulls on the other water molecules through their cohesive hydrogen bonds. This bonding extends to the roots of the tree pulling water directly from the soil. As the water travels up the tree vein the process of adhesion, the hydrogen bonding of water to another molecule is employed to resist the forces of gravity.

2. Frozen Water Expands; When water freezes it becomes less dense than it is at its liquid form. This is important to prevent a runaway freezing effect on bodies of water. If water was more dense in solid form it would freeze at the surface and then sink to the bottom. This process repeated would consume all of the bodies of water with ice. Life in an ocean of solid ice would be difficult. However, frozen water is less dense than the liquid form, therefore it floats. Floating ice on bodies of water provides the additional benefit of insulation. The ice layer on the surface insulates the heat of the water below allowing for suitable water temperatures for life.

3. Water as a Solvent ; The polarity of the water molecule make water a great solvent. The water molecules surround the oppositely charged ions as a result of attraction to their polar charges. The water molecules create a hydration shell that separates the ions and the compound is dissolved. There are other nonionic polar molecules that can be dissolved in water. Water, as a solvent, is the essential substance in nearly all life functions.

4. The Moderation of Temperature by Water; A brief explanation of kinetic energy is important to the topic of moderation of temperature. Kinetic energy is the energy of motion. In a body of water the molecules of water are always moving. This movement of the molecules is kinetic energy. Heat is the measure of a substance’s kinetic energy as a result of the movement of its molecules. If you add up all the kinetic energy of all the molecules in a body of water you get the heat of that body. This means that heat is determined by volume unlike temperature which just states the obvious regardless of volume. Taking this all into account large bodies of water like the Pacific Ocean have an awful lot of heat.