Water is a fundamental and essential substance for life on Earth, covering approximately 71% of the planet’s surface. It is a unique compound composed of two hydrogen atoms bonded to one oxygen atom, forming the familiar H2O molecule. This simple yet powerful structure gives water its remarkable properties that are crucial for sustaining life and supporting various ecosystems.
Importance of Water
Water plays a vital role in numerous aspects of life, from supporting biological functions in organisms to shaping landscapes through erosion and deposition processes. It is essential for hydration, nutrient transport, temperature regulation, and waste removal in living organisms. Additionally, water serves as a solvent for many substances, facilitating chemical reactions and metabolic processes necessary for life.
Properties of Water
One of the most remarkable properties of water is its high specific heat capacity, which allows it to absorb and release large amounts of heat without significant temperature changes. This property is crucial for regulating Earth’s climate and maintaining stable temperatures in aquatic environments. Water also exhibits cohesion and adhesion, enabling it to form droplets, capillary action in plants, and surface tension on bodies of water.
Forms of Water
Water exists in various forms across the planet, including liquid, solid (ice), and gas (water vapor). The water cycle describes the continuous movement of water between these forms through processes such as evaporation, condensation, precipitation, and runoff. This cycle plays a critical role in distributing water resources around the globe and sustaining ecosystems.
Human Impact on Water
Human activities have significantly impacted water quality and availability worldwide. Pollution from industrial waste, agricultural runoff, plastic debris, and other sources has contaminated freshwater sources and marine environments, posing risks to human health and ecosystem stability. Over-extraction of groundwater for agriculture and urban development has led to depletion of aquifers and subsidence in some regions.
Sustainable Water Management
To ensure the availability of clean water for current and future generations, sustainable water management practices are essential. This includes conservation efforts to reduce water waste, implementing efficient irrigation techniques in agriculture, investing in wastewater treatment facilities to recycle water resources, and promoting awareness about the importance of preserving water quality.
Conclusion
In conclusion, water is a precious resource that sustains life on Earth in countless ways. Its unique properties and global distribution make it indispensable for ecosystems, human societies, and the planet as a whole. By understanding the significance of water, practicing responsible stewardship, and implementing sustainable management strategies, we can protect this vital resource for generations to come.
- https://en.wikipedia.org/wiki/Water – Water – This page provides an overview of water, including its chemical and physical properties, aquaphobia, human right to water and sanitation, hydroelectricity, and marine current power.
- https://en.wikipedia.org/wiki/Water_content – Water content – This page explains the concept of water content or moisture content, which is the quantity of water contained in a material such as soil, rock, ceramics, crops, or wood. It also describes the four standard water contents that are routinely measured and used.
- https://en.wikipedia.org/wiki/Water_resources – Water resources – This page explains water resources as natural resources of water that are potentially useful for humans, for example as a source of drinking water supply or irrigation water. It also provides a list of related topics such as water resources law, water rights, and virtual water.
- https://en.wikipedia.org/wiki/Properties_of_water – Properties of water – This page provides information on the properties of water, including its chemical formula, structure, and reactions. It also explains the anomalous properties of water, such as its high surface tension, boiling point, and heat capacity.
Water is an inorganic compound with the chemical formula H2O. It is a transparent, tasteless, odorless, and nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent). It is vital for all known forms of life, despite not providing food energy or organic micronutrients. Its chemical formula, H2O, indicates that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds. The hydrogen atoms are attached to the oxygen atom at an angle of 104.45°. In liquid form, H2O is also called "water" at standard temperature and pressure.
| |||
| |||
| |||
| Names | |||
|---|---|---|---|
| Preferred IUPAC name
Water | |||
| Systematic IUPAC name
Oxidane | |||
Other names
| |||
| Identifiers | |||
3D model (JSmol)
|
|||
| 3587155 | |||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| DrugBank | |||
| ECHA InfoCard | 100.028.902 | ||
| EC Number |
| ||
| 117 | |||
| KEGG | |||
PubChem CID
|
|||
| RTECS number |
| ||
| UNII | |||
CompTox Dashboard (EPA)
|
|||
| |||
| |||
| Properties | |||
| H 2O | |||
| Molar mass | 18.01528(33) g/mol | ||
| Appearance | Almost colorless or white crystalline solid, almost colorless liquid, with a hint of blue, colorless gas | ||
| Odor | Odorless | ||
| Density |
| ||
| Melting point | 0.00 °C (32.00 °F; 273.15 K) | ||
| Boiling point | 99.98 °C (211.96 °F; 373.13 K) | ||
| Solubility | Poorly soluble in haloalkanes, aliphatic and aromatic hydrocarbons, ethers. Improved solubility in carboxylates, alcohols, ketones, amines. Miscible with methanol, ethanol, propanol, isopropanol, acetone, glycerol, 1,4-dioxane, tetrahydrofuran, sulfolane, acetaldehyde, dimethylformamide, dimethoxyethane, dimethyl sulfoxide, acetonitrile. Partially miscible with diethyl ether, methyl ethyl ketone, dichloromethane, ethyl acetate, bromine. | ||
| Vapor pressure | 3.1690 kilopascals or 0.031276 atm at 25 °C | ||
| Acidity (pKa) | 13.995 | ||
| Basicity (pKb) | 13.995 | ||
| Conjugate acid | Hydronium H3O+ (pKa = 0) | ||
| Conjugate base | Hydroxide OH– (pKb = 0) | ||
| Thermal conductivity | 0.6065 W/(m·K) | ||
Refractive index (nD)
|
1.3330 (20 °C) | ||
| Viscosity | 0.890 mPa·s (0.890 cP) | ||
| Structure | |||
| Hexagonal | |||
| C2v | |||
| Bent | |||
| 1.8546 D | |||
| Thermochemistry | |||
Heat capacity (C)
|
75.385 ± 0.05 J/(mol·K) | ||
Std molar
entropy (S⦵298) |
69.95 ± 0.03 J/(mol·K) | ||
Std enthalpy of
formation (ΔfH⦵298) |
−285.83 ± 0.04 kJ/mol | ||
Gibbs free energy (ΔfG⦵)
|
−237.24 kJ/mol | ||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards
|
Drowning Avalanche (as snow) Water intoxication | ||
| NFPA 704 (fire diamond) | |||
| Flash point | Non-flammable | ||
| Safety data sheet (SDS) | SDS | ||
| Related compounds | |||
Other cations
|
|||
Related solvents
|
|||
| Supplementary data page | |||
| Water (data page) | |||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |||
Because Earth's environment is relatively close to water's triple point, water exists on Earth as a solid, a liquid, and a gas. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds consist of suspended droplets of water and ice, its solid state. When finely divided, crystalline ice may precipitate in the form of snow. The gaseous state of water is steam or water vapor.
Water covers about 71% of the Earth's surface, with seas and oceans making up most of the water volume (about 96.5%). Small portions of water occur as groundwater (1.7%), in the glaciers and the ice caps of Antarctica and Greenland (1.7%), and in the air as vapor, clouds (consisting of ice and liquid water suspended in air), and precipitation (0.001%). Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.
Water plays an important role in the world economy. Approximately 70% of the fresh water used by humans goes to agriculture. Fishing in salt and fresh water bodies has been, and continues to be, a major source of food for many parts of the world, providing 6.5% of global protein. Much of the long-distance trade of commodities (such as oil, natural gas, and manufactured products) is transported by boats through seas, rivers, lakes, and canals. Large quantities of water, ice, and steam are used for cooling and heating in industry and homes. Water is an excellent solvent for a wide variety of substances, both mineral and organic; as such, it is widely used in industrial processes and in cooking and washing. Water, ice, and snow are also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, diving, ice skating, snowboarding, and skiing.
English
Wikiquote
Wikiversity
Pronunciation
- (Received Pronunciation) IPA(key): /ˈwɔːtə/, enPR: wôˈ -tə
- (Standard Southern British) IPA(key): /ˈwoːtə/, [wo̞ːtʰə], [wo̞ːʔə]
- (General American) IPA(key): /ˈwɔtəɹ/, [ˈwɔɾɚ], enPR: wôtər
- (cot–caught merger) IPA(key): /ˈwɑtəɹ/, [ˈwɑɾɚ], enPR: wätər
- Rhymes: -ɔːtə(ɹ), -ɒtə(ɹ)
- Hyphenation: wa‧ter
Etymology 1
From Middle English water, from Old English wæter (“water”), from Proto-West Germanic *watar, from Proto-Germanic *watōr (“water”), from Proto-Indo-European *wódr̥ (“water”).