Water

liquid

1 kg/l

H2O

slightly light blue clear liquid (appears colourless in small volumes)

water, i.e. hydrogen monoxide, is one of the most popular substances in the universe, the most popular liquid on Earth; under standard conditions it exists as a liquid, but it easily changes its states of matter, the freezing point is 0 degrees Celsius, while its boiling point is 100 degrees Celsius; water is a very good solvent for both inorganic and organic compounds, it is considered an universal solvent; chemically pure water is also characterized by very low conductivity, only aqueous solutions have the ability to conduct electricity; water is also characterized by high surface tension; it is the result of electrostatic interactions between water molecules; thanks to it, water strives to have as little surface as possible, which is why water drops take the shape of a ball; the surface tension of water, like many other features, depends on temperature - it decreases as it increases

water is the basic raw material used by humans, it is necessary for the proper functioning of our body (it is recommended to drink about 2 liters of water a day), it is used by us in our households for washing, cleaning, bathing, etc.; it is used on a massive scale in the production of food, but also in the production of various items that surround us every day, such as telephones, furniture, asphalt and much more; it is used in the construction of all kinds of buildings and structures that surround us; is used as a source of so-called "green energy", power plants are built based on the energy of flowing water (about 15% of the energy produced by humans comes from hydroelectric power plants); in fact, water is used in every field that surrounds us

despite the fact that water covers about 75% of the surface of our planet, it is still unknown how it got there (it was most likely free or in the form of other compounds during the formation of the Earth); the slightly blue colour of water results from its absorption of electromagnetic radiation in the visible light range corresponding to the red colour (red light is absorbed by water about 100 times stronger than blue light); water, as one of the few substances, does not increase its volume with increasing temperature in the entire area of its existence in the liquid state, but has a minimum value of 3.98°C; at temperatures lower than this value, the volume of water increases as the temperature decreases, which is an anomaly among all chemical substances; in the past, water was considered a symbol of purification and purity, and in many religions, purification takes place through symbolic immersion in water