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Sunday, 25 January 2015

The Water

Water


CAS-No. 7732-18-5
formula H2O
Molar mass (1) ... 18.01471
18.01599 g / mol
Melting point of 0.0 ° C
Boiling point 99.97 ° C
density
3.98 ° C
20 ° C
1.00g / cm3
0.998203 g / cm3
Refractive index [25 ° C] 1.33251
Dielectric constant. [20 ° C] 80.35

Water is the liquid which dissolves in many more substances (universal solvent), this property is due to its ability to form hydrogen bonds with other substances, as these will dissolve when interacting with the polar water molecules.

Solvent capacity is responsible for two important roles for living things: the environment in which run the majority

Reactions of nutrient supply and metabolism and waste disposal are done through aqueous transport systems.


A 20 540 calories for a gram of water evaporation is needed, which is indicative of the energy required to break the hydrogen bonds between the molecules set of liquid water and subsequently to provide these molecules sufficient kinetic energy to leave phase transition to the liquid and vapor.