Water

Water (chemical formula: H₂O) is a transparent fluid which forms the world's streams, lakes, oceans and rain, and is the major constituent of the fluids of organisms. As a chemical compound, a water molecule contains one oxygen and two hydrogen atoms that are connected by covalent bonds. Water is a liquid at standard ambient temperature and pressure, but it often co-exists on Earth with its solid state, ice; and gaseous state, steam (water vapor). It also exists as snow, fog, dew and cloud.

Water covers 71% of the Earth's surface. It is vital for all known forms of life. On Earth, 96.5% of the planet's crust water is found in seas and oceans, 1.7% in groundwater, 1.7% in glaciers and the ice caps of Antarctica and Greenland, a small fraction in other large water bodies, and 0.001% in the air as vapor, clouds (formed of ice and liquid water suspended in air), and precipitation. Only 2.5% of this water is freshwater, and 98.8% of that water is in ice (excepting ice in clouds) and groundwater. Less than 0.3% of all freshwater is in rivers, lakes, and the atmosphere, and an even smaller amount of the Earth's freshwater (0.003%) is contained within biological bodies and manufactured products. A greater quantity of water is found in the earth's interior.

Water vapor

Water vapor, water vapour or aqueous vapor, is the gaseous phase of water. It is one state of water within the hydrosphere. Water vapor can be produced from the evaporation or boiling of liquid water or from the sublimation of ice. Unlike other forms of water, water vapor is invisible. Under typical atmospheric conditions, water vapor is continuously generated by evaporation and removed by condensation. It is lighter than air and triggers convection currents that can lead to clouds.

Being a component of Earth's hydrosphere and hydrologic cycle, it is particularly abundant in Earth's atmosphere where it is also a potent greenhouse gas along with other gases such as carbon dioxide and methane. Use of water vapor, as steam, has been important to humans for cooking and as a major component in energy production and transport systems since the industrial revolution.

Water vapor is a relatively common atmospheric constituent, present even in the solar atmosphere as well as every planet in the Solar System and many astronomical objects including natural satellites, comets and even large asteroids. Likewise the detection of extrasolar water vapor would indicate a similar distribution in other planetary systems. Water vapor is significant in that it can be indirect evidence supporting the presence of extraterrestrial liquid water in the case of some planetary mass objects.

Water (Elitsa & Stoyan song)

"Water" (Bulgarian script: Вода) was the Bulgarian entry in the Eurovision Song Contest 2007, performed in Bulgarian by Elitsa Todorova & Stoyan Yankoulov. This was the first occasion on which the Bulgarian language was used on the Eurovision stage, previous Bulgarian entries being performed in English. Originally titled "Voda", the song had its title translated to English for the Contest.

The song is an up-tempo number with techno influences, as well as a jaw harp and traditional percussion. Todorova sings folk-inspired lyrics dealing with a young girl meeting a young boy riding a horse.

The performance in the semi-final featured the duo wearing what looked like armour, while they were wearing more mainstream clothes in the final. The performances were also notable for the high-energy percussion performances of both musicians.

As Bulgaria had not finished the previous Contest in the top ten, the song was performed in the semi-final. Here, it was performed first (preceding Israel's Teapacks with "Push The Button"). At the close of voting, it had received 146 points, placing 6th in a field of 28 and qualifying Bulgaria for its first final.