All the theory of the origin of life on Earth in some way connected with the water.She is standing beside us, in fact, within us.The most common, plain water included in the tissues of the body, makes it possible to each new breath and heartbeat.In all these processes it is involved because of its unique properties.
What is water: determination
From a scientific point of view, the primary fluid of the planet is an oxide of hydrogen - a binary inorganic compound.The molecular formula of water is perhaps known to all.Each structural element it consists of one oxygen atom and two hydrogen atoms linked polar covalent bond.Under normal conditions, it is in a liquid state, has no taste or smell.Smaller quantities of plain water without admixtures are colorless.
biological role
Water - the main solvent.That is the nature of the molecular structure makes it possible to such a definition.The properties of the water associated with it polarisability: each molecule has two poles.Negative bound with oxygen and the positive - with hydrogen atoms.A water molecule is capable of forming the so-called hydrogen bonds with other particles of matter, atoms are pulling oppositely charged to its "+" and "-".Thus a substance which becomes a solution should also be polarized.One molecule of it is surrounded by several water particles.After converting the substance becomes more reactivity.As the solvent, water is used by all cells of living organisms.This is one of those properties that determine its biological role.
Three states
Water is known to us in three forms: liquid, solid and gaseous.The first of these states of aggregation as mentioned above, is typical of water under ambient conditions.At normal atmospheric pressure and temperatures below 0 ° C it becomes ice.If the heating of the substance up to 100 ° C, formed from the liquid vapor.
It should be noted that similar in structure to the substance under normal conditions are gaseous and have a low boiling point.The reason for the relative stability of water - in the hydrogen bonds between molecules.To go into a state of steam is necessary to break them.Hydrogen bonds are strong enough to destroy them, and requires large amounts of energy.Hence, a high boiling point.
Surface tension
through hydrogen bonding of water is characterized by high surface tension.In this regard, it is second only to mercury.Surface tension occurs at the boundary of two different environments and requires the expenditure of a certain amount of energy.The result of this property is interesting effects.In weightlessness drop takes a spherical shape, since the liquid tends to reduce its own surface to conserve energy.Similarly, the water behaves sometimes on nonwettable materials.Example - a drop of dew on the leaves.Through the power of the surface tension on the surface of the pond skaters can slide and other insects.
insulator or a conductor?
on lessons on life safety for children is often explained that the water is a good conductor of electricity.However, this is not true.Because of the structure of its clean water weakly dissociated and non-conducting.That is, in fact, it is an insulator.However, under normal conditions meet so pure water is practically impossible as it dissolves many substances.And thanks to the numerous impurities liquid becomes a conductor.Moreover, the ability to conduct electricity, you can determine how much water is clean.
refraction and absorption
Another feature of water known since high school all - the ability to refract light rays.After passing through the liquid light of several changes in direction.With this effect associated with the formation of the rainbow.Also, the refraction of light, and our perception of it form the basis of errors in determining the depth of the water: it always seems smaller than it actually is.
however refracted light of the visible spectrum.And, for example, infrared rays are absorbed by water.That is why there is a greenhouse effect.To understand the hidden features of water in this sense, we can refer to the characteristics of the atmosphere of Venus.According to one version to the greenhouse effect on the planet resulted in the evaporation of water.
water color
Anyone who has seen the sea, or any fresh water body and compared it with the liquid in the glass, noticed some discrepancy.The color of water in natural or artificial water reservoir never coincides with that observed in the cup.In the first case it's blue, blue, even green-yellow, the second is simply not available.So what color is the water really?
turns out that is not pure liquid is colorless.She has a slight bluish tinge.The color of the water is so pale that in small quantities it seems to be absolutely transparent.However, under natural conditions, it appears in all its glory.Moreover, numerous impurities as in the case of electricity, change properties of water.All met at least once a pond green or brownish puddles.
color of the water and the life
Painting pond often depends on the microorganisms actively breeding in it of the impurity of rocks.The greenish color of the water often indicates the presence of small algae.In sea areas painted in this group usually abound in animals.Therefore, the fishermen always pay attention to the color of the water.The pure blue waters are poor in plankton, and, therefore, those who feed on them.
Sometimes microbes give the most bizarre shades.There are lakes with chocolate water color.The activity of single-celled algae and bacteria made turquoise pond on the island of Flores in Indonesia.
Switzerland Sanetsch pass on a lake with bright pink water.A little more than a pale shade of a body of water in Senegal.
Colorful miracle
striking sight appears to tourists in America, Yellowstone National Park.There is a lake Morning Glory.Its waters are clear blue color.The reason for such color - the same bacterium.Yellowstone is famous for its numerous geysers and hot springs.At the bottom of the lake Morning Glory is located a narrow vent.Rising out heat and keeps the water temperature as well as the development of bacteria.Once the entire lake was crystal blue.But over time, clogged vent, which contributed to the tourists and with his love to throw coins and other debris.As a result, the surface temperature decreased, it began to reproduce other types of bacteria.Today, painting water changes with depth.At the bottom of the lake is still deep blue.
few billion years ago, the water contributed to the emergence of life on Earth.Since then, its value does not decrease.Water is essential for a number of chemical reactions at the cellular level, it is a part of all tissues and organs.Oceans cover about 71% of the planet's surface and plays a huge role in maintaining the stability of the state of such a huge system like the Earth.Physical and chemical properties of water make it possible to call it the main material for all living things.Reservoirs, being the habitat of multicellular organisms, moreover, become a source of beauty and inspiration, demonstrate enormous creativity of nature.
