Water

Water, known scientifically as dihydrogen monoxide, was a compound created from the elements of hydrogen and oxygen and found on many planets in the galaxy. The surface of planets such as Mon Calamari, Kamino, and Manaan were completely covered in water and on other terrestrial planets, water was found in oceans, lakes, rivers and aquifers. Water was a vital commodity for many life forms, while for other species it was poisonous. Bodies of many species consisted of large amounts of water; for example, water was about 60 percent of Human body weight.

Water in its frozen form was known as ice and in gaseous form was called water vapor, which formed crystals. Sometimes it would condense and fall as snow, sleet, or hail. Planets that experienced consistent ice included Csilla, Hoth, Mygeeto, Ilum, Rhen Var, Anteevy, Ota, Orto Plutonia, Ojom, Rekkiad, and Polus.

In the galaxy, no liquid was as versatile as water, and few organisms could exist without it. The unique molecular structure of water gave it several unusual properties necessary to the chemical reactions that sustained life. These properties included its ability to dissolve chemicals, its ability to easily absorb and redistribute heat, its high surface tension, and the fact that it expanded when frozen. Life had a much higher likelihood of developing where water and carbon were present.

Han Solo noted while on Tatooine that none of the millions of scientific geniuses in the galaxy had found a way to eliminate a human body's need for water. They could make suits that conserved every drop, they could build Chem-reactors that synthesized it out of any breathable atmosphere or pressurize it so that you could carry a week's supply on their belt in a mass-nulling clip. However, there was no pill or injection that negated the need for water.

Text and facts from the “Water/Legends” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.