Water and ..: Physicochemical properties and Biological Importance

WATER The world's surface is made up to 71 percent water- the majority is saltwater in the sea with the remaining freshwater in rivers, lakes, and glaciers. Without water life would be impossible. Life first began in water, and the bodies of all living things are mostly made of water. Water contains water, and the bodies of all living things are mostly made of water. Water contains minerals, which are picked up from the surrounding soil and rocks and exists as ice liquid, or steam. At 32o F (0o C) it freezes into solid ice. At 212o F (100o C) it boils into steam. Clouds are huge collections of water particles. Clouds contain millions of tons of water, which fall back to earth as rain. Some of this water stays in the soil or underground for years, but most of it returns to the oceans by the rivers or streams. The chemical formula of water is H2O. This means that each molecule is made up to two atoms of hydrogen and one atom of oxygen. By using two electrodes to pass electricity through water, it can be separated into hydrogen and oxygen gas. This process is known as electrolysis. Pisla Ionut Class a-XII-a A Grupul Scolar Foerestier Rucar- Romania.
WATER IN NATURE Water, air and land are the basic elements of the environment. Due to its rapid circuit in nature, water is one of the resources which can be removable. We find it in nature under the form of liquids, steam or ice. In atmosphere it may last a few hours, in lakes or rivers it lasts days, months and years or end. As for the seas, oceans or glaciers, water can last thousands of years. It played an important role in the appearance of life on the Earth. Without it, life is not possible because: Water keeps plants, animals and human beings alive; It facilitates the physical- chemical processes in living cells; It ensures lining conditions on the Earth. Man cannot survive without water more than 7-8 days. A healthy body needs 2,5 L a day (24 hours). That is why man has to keep water clean, to protect and maintain its qualities at a high level. Valimareanu Alexandru Class a-XI-a B Grupul Scolar Foerestier Rucar- Romania
WATER- TWO HYPROSTASES H2O- the formula of life Water has a strange behavior for a liquid: it dilates when it's freezing, instead of contracting, as the other compounds do. It has unexpected boiling and solidification points, comparing to those of similar structure: Hydrogen Selenide or hydrogen sulfuride. However, water is a chemical compound without which life, as we know today, would not have been possible on Terra. Having cooled the planet for more than four thousand million years with the help of its steams, it became "the solvent of life". Being indispensable in elaborating "prebiotic" compounds which preceded the a appearance of life on earth, water in liquid state made possible for a great quantity of carbonic gas to be stopped on the bottom of the oceans, as it seems to have happened on primitive Terra. This factor limited the global warming at a great rate and it facilitated the appearance of climatic conditions necessary in elaborating the molecules of biological interest. By considering after the cooling of Terra, the surface water give birth to the oceans in which life will appear. In fact the hypothesis regarding the appearance of life on earth suggests that, according to these condensing abd evaporating cycles the lakes and the seas were to be the only terrestrial landscapes in those primordial times. The latest spatial missions has revealed the hypothesis according to which the comets are made up of ice incorporated with different organic compounds. It is possible for a great quantity of water to have reached the earth during the period of unceaseingly attack of Terra by these celestial objects. Bordea Andreea Class a-XI-a B Grupul Scolar Foerestier Rucar- Romania.
WATER, ADVENTURE OF LIFE The first astronauts were impressed looking from the space. The Blue Planet: The ice was blue, the pure water was blue. This is due to the Terra could become the place of the appearance of life on the Earth. The sister planets, Mars, and Venus, couldn't benefit the some chance. Then the increased cooling, the existence of Carbon, Oxygen, Hydrogen and Nitrogen atoms, which penetrate in the warm mass, determine in time a state of non -gas and contribute to the molding of a cover which due to the gravitational force is stabilized for giving born to a pro- atmosphere, were the atomic shocks create the first simple molecules- the carbonic gas and the steams of water. This new atmosphere encourages the transformation of the steams into water which determined a series of transformations (changed). It was sufficient that the distance Earth to Sun to be inferior with a few degrees, so that the temperature too high from the surface of the Earth should maintain the water in a gaseous state, hindering the formation of the liquid areas. The adventure of life could have never had begun. Lutea Daniela Class a-XI-a B Grupul Scolar Foerestier Rucar- Romania.