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Watter (H
2
O
) is a polar inorganic compoond that is at ruim temperatur a tasteless an odourless liquid, nearly colourless wi a hint o blue. It is an important solvent an is kent as the "universal solvent" for its ability tae dissolve mony substances.[11]

Water (H
2
O)
The water molecule haes this basic geometric structur
Baw-an-stick model o a water molecule
Space fillin model o a watter molecule
A drop o watter fawin towards watter in a glass
Names
IUPAC name
water, oxidane
Ither names
Hydrogen oxide, Dihydrogen monoxide (DHMO), Hydrogen monoxide, Dihydrogen oxide, Hydrogen hydroxide (HH or HOH), Hydric acid, Hydrohydroxic acid, Hydroxic acid, Hydrol,[1] μ-Oxido dihydrogen
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
RTECS nummer ZC0110000
UNII
Properties
H
2
O
Molar mass 18.01528(33) g/mol
Appearance White solit or awmaist colorless, transparent, wi a slicht hint o blue, crystalline solit or liquid[2]
Odour None
Density Liquid: 999.9720 kg/m3 ≈ 1 tonne/m3 = 1 kg/l = 1 g/cm3 ≈ 62.4 lb/ft3 (maximum, at ~4 °C)

Solid: 917 kg/m3 = 0.917 tonne/m3 = 0.917 kg/l = 0.917 g/cm3 ≈ 57.2 lb/ft3
Meltin pynt 0.00 °C (32.00 °F; 273.15 K) [lower-alpha 1]
Bylin pynt 100.02 °C; 212.04 °F; 373.17 K [3][lower-alpha 1]
Solubility Poorly soluble in haloalkanes, aliphatic an aromatic hydrocarbons, ethers.[4] Improved solubility in carboxylates, alcohols, ketones, amines. Miscible wi methanol, ethanol, isopropanol, acetone, glycerol.
Vapour pressur At 25 °C, 3.1690 kilopascals or 0.031276 atm[5]
Acidity (pKa) 13.995 (at 25 °C)[6][lower-alpha 2]
Basicity (pKb) 13.995 (at 25°C)
Thermal conductivity 0.6065 W/m·K[8]
Refractive index (nD) 1.3325
Viscosity 0.890 cP (25 °C)[9]
Structur
Hexagonal
Pynt group C2v
Molecular shape Bent
1.85 D
Thermochemistry
Speceefic heat capacity, C 75.375 ± 0.05 J/mol·K[10]
Staundart molar
entropy
So298
69.95 ± 0.03 J/mol·K[10]
Std enthalpy o
formation
ΔfHo298
-285.83 ± 0.040 kJ/mol[4][10]
-237.24 kJ/mol[4]
Hazards
Main hazards Drownin
Watter intoxication
Avalanche (as snaw)
(see an aa Dihydrogen monoxide hoax)
NFPA 704
Flammability code 0: Will nae burn. E.g., watterHealth code 0: Exposur unner fire condeetions would offer no hazard beyond that o ordinary combustible material. E.g., sodium chlorideReactivity code 0: Normally stable, even unner fire exposur condeetions, an is nae reactive wi watter. E.g., liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
0
0
0
Flash pynt Non-flammable
Relatit compoonds
Ither cations
Hydrogen sulfide
Hydrogen selenide
Hydrogen telluride
Hydrogen polonide
Hydrogen peroxide
Relatit solvents
Acetone
Methanol
Relatit compoonds
Watter vapor
Ice
Hivy watter
Except whaur itherwise notit, data are gien for materials in thair staundart state (at 25 °C [77 °F], 100 kPa).
YesY verify (whit is YesYN ?)
Infobox references

NotesEedit

  1. 1.0 1.1 Vienna Standard Mean Ocean Water (VSMOW), uised for calibration, melts at 273.1500089(10) K (0.000089(10) °C, an byles at 373.1339 K (99.9839 °C). Ither isotopic composeetions melt or byle at slichtly different temperatures.
  2. A commonly quotit value o 15.7 uised mainly in organic chemistry for the pKa o watter is incorrect.[7]

ReferencesEedit

  1. "Definition of Hydrol". Merriam-Webster. (Subscription required (help)). 
  2. Braun, Charles L.; Smirnov, Sergei N. (1993-08-01). "Why is water blue?". Journal of Chemical Education. 70 (8): 612. Bibcode:1993JChEd..70..612B. doi:10.1021/ed070p612. ISSN 0021-9584. 
  3. Water in Linstrom, P.J.; Mallard, W.G. (eds.) NIST Chemistry WebBook, NIST Standard Reference Database Number 69. National Institute of Standards and Technology, Gaithersburg MD. http://webbook.nist.gov (retrieved 2016-5-27)
  4. 4.0 4.1 4.2 Anatolievich, Kiper Ruslan. "Properties of substance: water". 
  5. Lide, David R. (2003-06-19). CRC Handbook of Chemistry and Physics, 84th Edition. CRC Handbook (in Inglis). CRC Press. Vapor Pressure of Water From 0 to 370° C in Sec. 6. ISBN 9780849304842. 
  6. Lide, David R. (2003-06-19). CRC Handbook of Chemistry and Physics, 84th Edition. CRC Handbook (in Inglis). CRC Press. Chapter 8: Dissociation Constants of Inorganic Acids and Bases. ISBN 9780849304842. 
  7. "What is the pKa of Water". University of California, Davis. 
  8. Ramires, Maria L. V.; Castro, Carlos A. Nieto de; Nagasaka, Yuchi; Nagashima, Akira; Assael, Marc J.; Wakeham, William A. (1995-05-01). "Standard Reference Data for the Thermal Conductivity of Water". Journal of Physical and Chemical Reference Data. 24 (3): 1377–1381. doi:10.1063/1.555963. ISSN 0047-2689. 
  9. Lide, David R. (2003-06-19). CRC Handbook of Chemistry and Physics, 84th Edition. CRC Handbook (in Inglis). CRC Press. 6-186. ISBN 9780849304842. 
  10. 10.0 10.1 10.2 Water in Linstrom, P.J.; Mallard, W.G. (eds.) NIST Chemistry WebBook, NIST Standard Reference Database Number 69. National Institute of Standards and Technology, Gaithersburg MD. http://webbook.nist.gov (retrieved 2014-06-01)
  11. "Water, the Universal Solvent". USGS.