Water (molecule) facts for kids
|Molecular formula||HOH or H2O|
|Molar mass||18.01524 g·mol−1|
colorless liquid with
a slight hint of blue
|see also||Water (data page)|
|Density and phase||1000 kg·m−3, liquid (4 °C)
917 kg·m−3, solid
|Melting point||0 °C, 32 °F (273.15 K)|
|Boiling point||100 °C, 212 °F (373.15 K)|
|Triple point||273.16 K, 611.73 Pa|
|Critical point||647 K, 22.1 MPa|
|cp=1970 J·kg−1·K−1 @ 300 K
cv=1510 J·kg−1·K−1 @ 300 K
|Viscosity||0.001 Pa·s at 20 °C|
|Surface Tension at 20 °C||7.28 N·m−1|
|Molecular shape||non-linear bent|
|Dipole moment||1.85 D|
|Supplementary data page|
|n, εr, etc.|
Solid, liquid, gas
|Spectral data||UV, IR, NMR, MS|
|Related compounds||water vapor
|Except where noted otherwise, data are given for
materials in their standard state (at 25 °C, 100 kPa)
Infobox disclaimer and references
At room temperature, it is a nearly colorless, flavorless, and odorless liquid. Many substances dissolve in water and it is commonly seen as the universal solvent; because of this, water in nature and in use is rarely clean, and may have some properties different than those in the laboratory. But there are many compounds that are essentially, if not completely, insoluble in water. Water is the only common, pure substance found naturally in all three states of matter—for other substances, see Chemical properties.
Pure water is tasteless. It is the other chemicals in the water which may give water a flavour.
Anomalous properties of water
Generally, the volume of a liquid increases when heated, however the volume of water decreases when heated within the temperature range of 0°C to 4°C. Its volume increases only when heated above 4°C. Such behavior is one of a number of water's anomalous properties.
This property of volume decrease allows fish and other aquatic animals to survive in a body of water when ice has frozen on the surface. In cold climates, when the temperature of a body of water reaches at 4°C, the layers of water near the top in contact with cold air continue to lose heat energy and their temperature falls below 4°C. On cooling below 4°C, these layers rise rather than sink, as water has maximum density at 4°C. Thus the layer of water with a temperature of 4°C remains at the bottom, while layers of water 3°C, 2°C, 1°C and 0°C are formed above. Because ice is poor conductor of heat, it does not allow heat energy transfer from the liquid water beneath the layers of ice, which prevents the liquid water from freezing. Hence, aquatic creatures survive in such places.
Images for kids
This paper clip is under the water level, which has risen gently and smoothly. Surface tension prevents the clip from submerging and the water from overflowing the glass edges.
Water (molecule) Facts for Kids. Kiddle Encyclopedia.