vattnet

Vattnet, commonly referred to as water, is the clear, essential liquid that makes up a large part of the Earth's hydrosphere and is vital for all known forms of life. Chemically, it consists of two hydrogen atoms bonded to one oxygen atom (H2O). The molecule is polar and forms hydrogen bonds, properties that give water a high surface tension, a high heat capacity, and a strong solvent ability. In nature it exists in three states—ice, liquid water, and water vapor—depending on temperature and pressure. The standard melting point is 0°C and the boiling point is 100°C at one atmosphere, though impurities and pressure modify these values.

Earth's water distribution shows that about 97.5% of global water is saline, found mainly in oceans. About 2.5% is freshwater, of which most is locked in glaciers, ice caps, or deep groundwater; only a small share is readily accessible in rivers, lakes, soils, and shallow aquifers. The water cycle transports and redistributes freshwater through evaporation, condensation, precipitation, infiltration, and run-off, driven by solar energy and atmospheric processes.

For humans, water is indispensable for drinking, cooking, sanitation, agriculture, industry, and energy production. Water quality is determined by factors such as pH, turbidity, mineral content, salinity, and microbial safety. Treatment and infrastructure are used to supply safe drinking water and to manage wastewater. Global challenges include scarcity in parts of the world, pollution, and the impacts of climate change, which underscore the need for sustainable water management and conservation.

In Swedish, vattnet refers to water in general or to a specific body of water.