Water

of the titles of this article is ambiguous. For further meanings see water (term clarifying).

Water (H ₂ O) is a chemical compound from the elements oxygen (O) and hydrogen (H).

the designation water for the liquid state of aggregation are particularly used. In the solid, thus frozen state, becomesit ice mentioned, in the gaseous condition water vapour or simply only steam.

alternative designations the word

water flowing is derived 11,2 water chemistry “ from old-high-German wazzar „dampness. The indogermanische word wadar already is in the Hethiti 3. Milleniumv.u.Z occupies.

Also the old-Greek word hydor (= water), from which all foreign words with the word component “- hydr (o) - “is derived, belongs to this family.

Other chemical names for water are:

• Hydrogen oxide a possible name for water. To consider: Itexist still further oxides of the hydrogen. See: Hydrogen oxides.
• Diwasserstoffmonoxid, hydrogen hydroxide, Dihydrogeniumoxid, Hydrogeniumoxid, Hydrogeniumhydroxid or Dihydrogenmonoxid

history of the water use

major item: History of the water use

the history of the human use of the water and thus that onethe hydrology, the water management and particularly the hydraulic engineering, is coined/shaped by a comparatively small number of basic motives. From first established becoming humans to the advanced cultures the antique one over the Middle Ages up to the modern times always stood in the centera conflict between a too much and a too little at water. It one was delivered thereby nearly always whether by Dürren the harvest was received or life and possession threatened floods. Without the knowledge from where the water came and wherewas, became it a the subject of the mythology and later also nature philosophy. This very day a privileged position comes to the water in most religions of the world, particularly, where the question of surviving the solution of the numerous water problemsdepended.

A goal it was to be become fair all requirements for use and also to each humans it being entitled part of the water be guaranteed. For this the water law became as one of the first legals form the joint founder of the first centralistic civilizations of Mesopotamien andEgypt, into the river valleys of China and India.

The long history of the water use shows up thereby, like mankind history altogether, not as a continuous development path. It was coined/shaped particularly by individual centers high water-economical standards as well as always recurring breaks,apart from often centuries long lasting stagnation phases. Like that the early water-structural plants thereby also were impressing, as largely innovation strength also showed up and creativity of our ancestors, in the long run were and depend also today still one on the nature, which one howeveronly in comparatively recent time began to understand really.

occurrence

earth

water seems up to now only on the planet to earth, on which other planets (like Pluto, Saturn, Jupiter) is it not yet proven,that there is water there. The largest parts of the earth are covered of the water, whereby this is particularly in the Southern Hemisphere the case and shows up as extreme at the water hemisphere. The supply of the population of world with hygenic and toxicological harmless Drinking water, as well as a sufficient quantity industrial water, represent one of the largest challenges of mankind in the next decades.

The water occurrences of the earth amount to about 1,386 million km ³, about which alone 1,338 million km³ (96.5%) to the seawater of the Weltmeere is allotted. Only 48 million km ³ (3.5%) of the terrestrial water are present as fresh water . With 24.4 million km ³ (1.77%) most fresh water participates as ice to Poland, Bind for glaciers and permafrost soils and thus not the use accessible. Constitutes a further important portion the groundwater with 23.4 million km ³ . The water of running waters and lake (190,000 km ³), the atmosphere (13,000 km³), the soil (16,500 km ³) and the organisms (1,100 km ³) is purely quantitatively quite insignificant in the comparison. However only a small part of the fresh water is also available as drinking water. Altogether 98,233 lies% of the water in liquid, 1.766% in firmer and 0.001% in gaseous form forwards. In its different forms the water exhibits thereby specific retention times and continual circulates in the global water circulation.

These portions are however only approachassignable and changed itself also strongly in the course of climatic history, whereby in the course of the global heating up of a rise of the water vapour portion one goes out.

origin of the terrestrial water

major item: Origin of the terrestrial water

the origin of the wateron earth, in particular the question, why on earth more waters occurs clearly than on the other earthsimilar planets, is until today not satisfying clarified. A part of the water might have resulted to that from the outgassing magma, thusin the long run from the interior of the earth originate. Whether thereby however the quantity of water can be explained, is doubtful. In addition, further large portions could by impacts of comets, transneptunischen objects or water-rich Asteroiden (Protoplaneten) from the outside rangesthe Asteroidengürtels come on earth its. Measurements of the abundance ratio from deuterium to Protium (D/H relationship) point thereby rather on Asteroiden, since in Wassereinschlüssen in carbonaceous Chondriten similar conditions were found as in oceanic water, whereas past measurements of this abundance ratioat comets and transneptunischen objects with terrestrial water agreed only bad.

solar system

outside of the earth comes likewise water pre into gigantic quantities, for it however only “thinly distributed”: Either as ice on other heavenly bodies or than Water vapour. As ice water in comets („dirty Schneebälle “) was proven, on Mars and on some moons of the outside planets. However the Saturnringe contains roughly about 20-30% so much water, as occurs on earth. Many references interpret on itthat Mars contained open water surfaces of its development in the early period. Among the moons the Jupitermonde Europe, Ganymed and Kallisto , all Saturnmonde and Uranusmonde ranks, the Neptunmonde (among other things Triton, the largest Neptunmond), as well as Charon, thatlargest well-known moon Plutos. There are referring to the presence of ice in Meteoritenkratern in pole proximity even with Merkur, the sun-next planet. It is possible that on the ground connection moon in the pole regions at the reason of deep Krater ice occurrences asRelikte of comet impacts survived. Such occurrences would be important water and sources of oxygen for future Mondbasen, are however until further notice speculative.

water molecule

major item: Water molecule

like each chemical compound from two nonmetals, then exists also water out Molecules. There the water molecule - as the following article text shows - is polar, a dipole, has water special characteristics:

• The anomaly of the water (it the highest density^, so that ice swims ) has with +4 o C,
• the highest thermal capacity of all liquids (75.366 J/K x mol according to 4.18 kJ/kg x K)
• the largest surface tension of all liquids (with exception of mercury; with water them amount to in damp air 72 mN/m with +20 ^o C, so that thoseDroplet formation is facilitated),
• the largest evaporation enthalpy of all liquids (40.7 kJ/mol according to 2256 kJ/kg; therefore the refreshing effect with the transpiration) as well as high bloom an enthalpy (6.01 kJ/mol according to 333 kJ/kg; so that seawater an only small freezing point depression in the comparisonto pure water) and
• a very small heat conductivity points (so that oceans good heat accumulators are).

These material properties become ago explainable by the structure of the water molecules: It is bent, polar and of the formation of hydrogen bonds capable.

The molecule of the water existsfrom two hydrogen atoms and an oxygen atom. Geometrically the water molecule is bent, so that the two hydrogen atoms and the two pairs of electrons are arranged into the corners of a meant tetrahedron. The angle, that the two O-H-connections include amounts to 104,45°. It yieldsdue to the increased space requirement of the free pairs of electrons of the ideal Tetraederwinkel (~109,47°) off. The connection length of the O-H-connections amounts to in each case 95.84 pico-meters.

Oxygen has a higher Elektronegativität than hydrogen with 2,1 in the Pauling scale with 3,5. The water molecule points thereby pronounced Partialladungen up. Into combination with triangular geometry it comes on the side of the oxygen to a negative and on the side of the two hydrogen atoms to a positive polarity. This causes the dipole moment, that in the gaseous phase 1,84 Debye amounts to.

Water molecules interact with one another over hydrogen bonds and possess thereby pronounced between-molecular attraction. It concerns thereby no steady, firm concatenation. The group of the water molecules concatenated inconsistantly over hydrogen bonds exists only fractions of seconds, according to which itself the individual moleculesthe group solve and in a just as short period concatenate themselves again. This procedure constantly repeats itself and leads finally to the training of a variable cluster. Thereby important characteristics are caused like the anomaly of density.

Depending upon isotope composition of theWater molecule differentiates between one „heavy water “, „halfheavy water “and „overheavy water “. The mol masses amount to approx. 18 g/mol (H ₂ O), 19 g/mol (HDO), 20 g/mol (D ₂ O, HTO), 21 g/mol (DTO) and 22 g/mol(T ₂ O).

synthesis, electrolysis and proof

water as chemical compound were for the first time synthesized, as Henry Cavendish in 18. Century a mixture from hydrogen and air to the explosion brought.

There hydrogen in the future source of energywill is, is planned, to win by the electrolysis of the water this hydrogen. However a high energy expenditure for the electrolysis is necessary. Meanwhile researchers succeeded in splitting water up by presence of a catalyst only by means of sunlight into oxygen and hydrogen.One can divide the water molecules also in a hoffmannschen water decomposition apparatus into its components.Reaction pattern:

<math> \ mathrm {2 \ H_2O \ rightarrow 2 \ H_2 + O_2}< /math>

Proof reaction: Water colors white copper sulfate light blue and blue cobalt (II) - chloride paper is colored red by water.

meaning of the water in the sciences

water plays a central role in many sciences and areas of application because of its special chemical and physical characteristics, above all the dipole moment, the hydrogen bond and the anomaly of density. The science,which with the spatial like temporal distribution of the water and its characteristics is occupied, one calls hydrology. In particular the Ozeanologie examines the water of the Weltmeere, the Limnologie the water of the inland waters, the Hydrogeologie the groundwater and the Aquifere, the meteorology the water vapour of the atmosphere and the glaciology the frozen water of our planet. In liquid form water was proven so far only on earth.

„the anomaly of the water “

water has underNormal print with 3,98 °C the smallest volume and the largest density (0.999972 g/cm ³). Therefore it stretches - if one from this initial test temperature goes out itself - both when heating up and with cooling out (density drops in both directions).

Apart from „the anomaly of the water “there are 41 well-known anomalies with the water altogether. See Web on the left of: „41 anomalies of the water (English) “

major item: Characteristics of the water, material data of the water

(see also: Multimedialinks: Alpha Centauri is water magically?)

Meaning of the water for the life

it is the probable developing place of the terrestrial life and perhaps also a condition for this. In organisms and in dead components of the Geosphäre it plays as prevailing medium with nearly all metabolic procedures and/or geological and ecological Elementarprozessen a crucial role. The earth's surface is covered to about 72% of water, whereby oceans carry hieran the largest portion. Fresh water reserves form only 2.53% of the terrestrial water and only 0.3% are as drinking waterto open (Dyck 1995). By the role of the water regarding weather and climate, when Landschaftsgestalter is in the course of the erosion and by its economic meaning among other things in the ranges that country - , forest - and energy industrythis besides in various way with history, economics and culture of the human civilization connected.

For meaning for the life and the world see general: Meaning of the water

water chemistry

chemistry is occupied among other things with that Analysis of materials loosened in the water, the characteristics of the water, its use, its behavior in different connections. Water is a solvent for many materials, for ionic compounds, in addition, for hydrophilic gases and hydrophilic organic compounds. Even generally as in waterunsolvably valid connections are contained in traces in the water. Therefore water on earth is not present anywhere in pure condition. It loosened the most different materials depending upon origin in more or less large concentrations in itself. In analyticsone differentiates between the among other things following water types:

• High-purity water
• demineralized water
• distilled water
• snow and ice removal width unit water
• ethereal water
• Rohwasser
• rain water
• groundwater
• Oberflächenwasser (flowing and standing waters),
• fresh water/seawater/brackish water
• mineral water
• drinking water
• waste water, (household waste water, agricultural waste water, industrial waste waters)

in addition, with the aqueous Leachings (Eluaten) of sediments, dredging, solids, wastes and soils water analytics are used.

Over the characteristics of the water and possibly materials solved in it, and/or. thus in contact of standing firm phases to clear up the molecular dynamics have themselves - simulation works satisfactorily.

See also: Water in the geosciences the Icelandic Geysir

the outbreak in the geosciences

Hydrophobie, Hydrophilie [work on] briefly, which are particularly occupied with the water: the Hydrogeologie, those Hydrology, the glaciology, the Limnologie, the meteorology and oceanography. Particularly interesting for the geosciences, like water the landscape is changed (of small changes during a large period up to disasters, with those water withinfewer hours whole regions destroyed), this happens for example in the following ways:

• Rivers or seas tear earth masses with itself and give them again off in other place (erosion).
• Whole landscapes are transformed by moving glaciers.
• Water becomesby stones stored, freezes in these and blows up the stones apart, because it expands when freezing (frost decomposition).
• The natural ecological systems are strongly affected by Dürren.

Water is not only an important factor for the mechanical and chemicalErosion of rocks but also for the klastische and chemical sedimentation of rocks. Thus among other things groundwater leader develops.

Also geo scientist particularly interests the forecast of the weather and from rain events (meteorology).

See also: Waters, glacier, Permafrostboden, Binnenmeer, lake, pond, sea, ocean, river, brook, Flussaue.

water in hydrodynamics

the different flowtechnical the characteristics and wave modes on microscopic and macroscopic level are examined intensively, whereby the followingQuestions in the center stand:

• Optimierung von Bootskörpern und exponierter Baukörper (zum Beispiel Wehre) - Minimierung des Strömungswiderstandes
• Optimierung des Wirkungsgrades von wassergetriebenen Turbinenrädern
• Untersuchung von Strömungsphänomenen und Resonanzkatastrophen (Tsunami, Monsterwellen)
• Untersuchung der Konsistenz und Qualität desMedium water from the analysis of its characterizing flow characteristics. With this aspect Institut for flow sciences in Herrischried in the south Black Forest concerns itself.

cultural meaning of the water

due to the great importance of the water became it not coincidentally alreadywith the earliest philosophers ranked among the four Urelementen. Thales of Milet saw the element all Seins in the water even.

water in the antique sciences and philosophy

water is in from Empedokles the introduced and thenparticularly of Aristoteles represented four-element teachings beside fires, air and earth an element.

Likewise water is represented in the taoistischen five-element teachings ( beside wood, fire, earth, metal). Here however something is misleading the designation of elements, there it itself overdifferent aspects of transformation of a cyclic process acts.

In the antique Greece water the icosahedron was assigned to the element as one of the five Platonic bodies.

water in the religion

in the religions has water frequently a high value. Often becomescleaning Kraft of the water swore to, for example in the Islam in form of the ritual foot washing before entering a mosque, or in the Hindu faith with the ritual bath under way. In the Judentum as well as each municipality a Mikwe possesses, inRitual bath with flowing pure water, which often consists of a deeply handing groundwater well, if spring water is not available. Only who submerges itself completely, ritually cleaned. This is necessary not only for women after Menstruation or birth, but alsofor to the Judentum Bekehrte - similar a Christian baptism - or with orthodox Jews before the Sabbat and before holidays.

The Christian baptism was carried out in the late Middle Ages by submerging or pouring over with water as complete body baptism, in the west todayusually only by Besprengen with water. The baptism means turn to Christ and admission into the church. It stands also symbolically for dying (submerge) and Auferstehen (arrive on the bank of the new life). In the catholic and orthodox church playsthe Weihwasser a special role. Above all cleaning Kraft of the water cause gave again and again to think about the meaning of the water for the life and also for a life after death.

water as drinking water andProduct

for potable water supply usable water occurrences distinctive with respect to precipitation water, Oberflächenwasser with respect to rivers, lakes, dams, groundwaters, mineral waters and spring waters. The use of waters becomes in the water conservation law (in Germany, Austria and Switzerland (?)) regulated.In Central Europe there is a reliable, to a large extent cost-hitting a corner and high-quality water supply, usually still by public offerers. Usually tap water comes from the closer region, for which the local servicer takes also ecologically responsibility. The world-wide water market has a growth like hardlyanother industry. Therefore private offerers have large interest to define water as commodity in order to take over this market.

Even if the normal drinking water does not represent directly a commodity, then also from some organizations into the meeting it is led that throughthe globalization also an indirect water export, above all the countries of the third world, takes place. That means for example that for the cultivation of bananas 1,000 l/m ² soil is necessary. By production increases, which are intended for the export, the water is missing to thatnative population. (Source: Wuppertaler Institut)

water consumption

water does not disappear simply. “Consumption” is the loss of the technical (evaporation) and ecological use of the water by unwanted or harmful materials. (See also: Mass conservation law and water quality)Therefore the water consumption is the water needed for human consumption. This covers the direct human benefit (drinking water) just like to everyday lives (washes, cooking etc.) as well as for the agriculture, the trade and the industry (see Industrial water) given need. The water consumption is not therefore only a characteristic for the inquired quantity of water, but mostly also for the disposal (drains, purification plant)

the water requirement in Germany amounted to 1991 47.9 billion m ³, about which alone29 billion m ³ as cooling water in power stations served. Approximately 11 billion m ³ directly by the industry were used, 1.6 billion m ³ of the agriculture. Only 6.5 billion m ³ served the potable water supply. The average water consumption amounts to approximately130 litres per inhabitants and day (of it about 1 litre for drinking, beside Cola, beer or other beverages, which likewise contain water).

See also: Waste water, industrial water, consumption, water consumption

water supply

with clean water to renewing fresh water per inhabitants and year in the developing countries before a large logistic problem. Only 0.3% of the world-wide stores of water are available as drinking water, that are 3,6Millions km ³ of altogether approx. 1,38 billion km ³.

Around the water scarceness in countries of light precipitation too lindern, already moves appearing ideas considered: thus one suggested dragging with tractors an enormous iceberg over the sea onlypartially would melt to catch and from the thawing out iceberg drinking water.

See also: Water distribution system, water purification, water treatment plant, water management, water keeping clean

legal bases and authorities

major items: Water law

the water-legal bases of the water management and public handlingwith water resources the water conservation law and the European water framework guideline form in Germany. Important authorities and institutions are:

• Water and navigation velvet
• LAWA (working group)

exhibitions and meetings approximately around the water

• from 2005 to 2014 the UN has to International action decade „water - source of the life “ called
• world water forum
• world water day
• museum water forum HWW (Hamburg water companies)

see also

• drinking water, mineral water - water as beverage
• brackish water, seawater and fresh water - kinds of water after Salzgehalt
• waters - general designationfor natural and artificial lodgements of water
• water quality class, Saprobie - representation and determination of the water quality of running waters
• water as commodity - environmental and resources conflicts
• Weihwasser - as symbol in religion history
• Aquaristik - Wasserökotope and its attitude
• Mpemba effect - anomaly withFreezing procedure
• ice
• Dihydrogenmonooxid
• water (material data)

literature

general contents of

• Vollrath Hopp: Water - crisis? Water, nature, humans, technology and economics. Wiley VCH, Weinheim 2004, ISBN 3-527-31193-9
• Karl Höll, Andreas Grohmann et. aluminium: Water. Use inCycle. Hygiene, analysis and evaluation. 8. Edition. Walter de Gruyter, Berlin - New York, 2002.
• Dyck & Peschke (1995): Bases of the hydrology. 3. Edition, publishing house building industry. ISBN 3345005867
• Philip ball: H ₂ O - biography of the water. Piper publishing house, 2001, ISBN 3492041566

water chemistry

• Günter how/as country (1999): Water chemistry. 12. Edition, meal. ISBN 3802725425
• Bernd Naumann (1994): Chemical investigations of the base of life water. Publisher: Landesinstitut for teacher advanced training, teacher further training and instruction research of Saxonia-Anhalt (LISA)], (Bd =Anregungen for ecological education. ), resounds to 2.

use and protection

• Properties OF Water and Steam in SI units, thermodynamic characteristics of water and water vapour, 0 800 °C, 0 1000 bar; Springer publishing house 1981 ISBN 3-540-09601-9, ISBN 0-387-09601-9
• Christian Opp (Hrsg.): Water resources - useand protection (=Beiträge for the international year of the fresh water 2003) Marburg/Lahn 2004, 320 S., ISBN 388353049

health/Esoterik

• F. Batmanghelidj: Water - the healthy solution. A Umlernbuch. VAK publishing house, 2002. ISBN 3924077835
• F. Batmanghelidj: They are not ill, youare thirsty! Healing from the inside with water and salt. VAK publishing house, 2003, ISBN 3935767250
• Ebba Waerland: The meaning of the water drinking, Humata publishing house, ISBN 3-7197-0298-7

Web on the left of

Wiktionary: Water - word origin, synonyms and translations

Commons: Water - pictures,Video and/or audio files

Wikiquote: Water - quotations

general contents of

• quarks & CO: Life-pour water pdf
• water encyclopedia of the University of Bremen
• water moving way
• information about water
• research group (English)
• 41 anomalies of the water (English)

information to the water for children

• with a class wasser.de
• water drop on journeys
• Water environment

Multimedialinks

• material video (from the television broadcast alpha Centauri):
  • Is water magic?

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