Water

It forms precipitation in the form of rain and aerosols in the form of fog.

Rain is liquid water in the form of droplets that have condensed from atmospheric water vapor and then become heavy enough to fall under gravity.

Clouds are formed from suspended droplets of water and ice, its solid state.

Ice is water frozen into a solid state.

It forms precipitation in the form of rain and aerosols in the form of fog.

Fog is a visible aerosol consisting of tiny water droplets or ice crystals suspended in the air at or near the Earth's surface.

Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.

The water cycle, also known as the hydrological cycle or the hydrologic cycle, describes the continuous movement of water on, above and below the surface of the Earth.

The gaseous state of water is steam or water vapor.

Steam is water in the gas phase, which is formed when water boils or evaporates.

Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.

Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers.

Its chemical formula is H 2 O, meaning that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds.

Most of the mass of living organisms is oxygen as a component of water, the major constituent of lifeforms.

Clouds are formed from suspended droplets of water and ice, its solid state.

Water or various other chemicals may compose the droplets and crystals.

Its chemical formula is H 2 O, meaning that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds.

At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H 2 . Since hydrogen readily forms covalent compounds with most nonmetallic elements, most of the hydrogen on Earth exists in molecular forms such as water or organic compounds.

Water is an excellent solvent for a wide variety of chemical substances; as such it is widely used in industrial processes, and in cooking and washing.

Washing is a method of cleaning, usually with water and often some kind of soap or detergent.

Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, and diving.

Boat racing is a sport in which boats, or other types of watercraft, race on water.

Water is a polar inorganic compound that is at room temperature a tasteless and odorless liquid, nearly colorless with a hint of blue.

While relatively small quantities of water appear to be colorless, pure water has a slight blue color that becomes a deeper blue as the thickness of the observed sample increases.

It is vital for all known forms of life, even though it provides no calories or organic nutrients.

Foods are composed chiefly of carbohydrates, fats, proteins, water, vitamins, and minerals.

This effect is important in, among other things, deep-sea hydrothermal vents and geysers, pressure cooking, and steam engine design.

A hydrothermal vent is a fissure on the seafloor from which geothermally heated water issues.

This simplest hydrogen chalcogenide is by far the most studied chemical compound and is described as the "universal solvent" for its ability to dissolve many substances.

Water, the first chemical compound in this series, contains one oxygen atom and two hydrogen atoms, and is the most common compound on the Earth's surface.

Thus aquatic plants, algae, and other photosynthetic organisms can live in water up to hundreds of meters deep, because sunlight can reach them.

This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water – hence the name photosynthesis, from the Greek φῶς, phōs, "light", and σύνθεσις, synthesis, "putting together".

Water is a polar inorganic compound that is at room temperature a tasteless and odorless liquid, nearly colorless with a hint of blue.

Some materials, such as plate glass and clean water, transmit much of the light that falls on them and reflect little of it; such materials are called optically transparent.

It is vital for all known forms of life, even though it provides no calories or organic nutrients.

They are sourced from inorganic matter (for example, carbon dioxide, water, nitrates, phosphates, sulfates, and diatomic molecules of nitrogen and, especially, oxygen) and organic matter (carbohydrates, lipids, proteins).

The refraction index of liquid water (1.333 at 20 C) is much higher than that of air (1.0), similar to those of alkanes and ethanol, but lower than those of glycerol (1.473), benzene (1.501), carbon disulfide (1.627), and common types of glass (1.4 to 1.6).

Glycerol has three hydroxyl groups that are responsible for its solubility in water and its hygroscopic nature.

Specifically, at a standard pressure of 1 atm, water is a liquid between 0 and 100 C. Increasing the pressure slightly lowers the melting point, which is about -5 C at 600 atm and -22 C at 2100 atm.

In the presence of nucleating substances, the freezing point of water is not always the same as the melting point.

The word "water" comes from Old English "wæter", from Proto-Germanic "*watar" (source also of Old Saxon "watar", Old Frisian "wetir", Dutch "water", Old High German "wazzar", German "Wasser", Old Norse "vatn", Gothic "wato"), from Proto-Indoeuropean "*wod-or", suffixed form of root "*wed-" ("water"; "wet").

An asterisk is used to mark reconstructed words, such as *' 'water', *' 'dog' (English hound), or * 'three (masculine)'.

The interactions between water and the subunits of these biomacromolecules shape protein folding, DNA base pairing, and other phenomena crucial to life (hydrophobic effect).

The hydrophobic effect is the observed tendency of nonpolar substances to aggregate in an aqueous solution and exclude water molecules.

Water is a good polar solvent, that dissolves many salts and hydrophilic organic molecules such as sugars and simple alcohols such as ethanol.

Salts that produce hydroxide ions when dissolved in water are called alkali salts.

Thus aquatic plants, algae, and other photosynthetic organisms can live in water up to hundreds of meters deep, because sunlight can reach them.

Aquatic plants require special adaptations for living submerged in water, or at the water's surface.

Many organic substances (such as fats and oils and alkanes) are hydrophobic, that is, insoluble in water.

In chemistry, hydrophobicity is the physical property of a molecule (known as a hydrophobe) that is seemingly repelled from a mass of water.