For other uses, see Water (disambiguation).WATER
"H2O" redirects here. For other uses, see H2O (disambiguation).
Water is an inorganic compound with the chemical formula H2O. It is a transparent, tasteless, odorless,[c] and nearly colorless chemical substance, and it is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent[19]). It is vital for all known forms of life, despite not providing food energy or organic micronutrients. Its chemical formula, H2O, indicates that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds.
Water covers about 71% of the Earth's surface, with seas and oceans making up most of the water volume (about 96.5%).[22] Small portions of water occur as groundwater (1.7%), in the glaciers and the ice caps of Antarctica and Greenland (1.7%), and in the air as vapor, clouds (consisting of ice and liquid water suspended in air), and precipitation (0.001%).[23][24] Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.
Building the right kind of PPPs depends on finding ways for both investors and users, upstream and downstream communities, and the environment to benefit. Investors need incentives that ensure appropriate returns, users need access to a properly defined service, while being protected from high prices when there is insufficient competition.
The SDG Summit, which seeks to unlock fresh ambition and resources ahead of our 2030 deadline for the SDGs, must have water at its center. Water goes across all the SDGs. Water goes across all sectors. Water must be at the heart of designing measurable and actionable policies on the ground.
Water is a Basic Human Need.
Without it survival is not possible. Every day, 2.1 billion people still wake up each morning without access to clean water. This means that millions of vulnerable families around the world do not drink, cook, or bathe with clean water.
For most rural schools and communities, access to clean water depends on outside NGOs (nonprofit organizations) purchasing or “giving” a well. However, there are millions of schools and communities that do not have access to nonprofit agencies or local government support. We must then ask ourselves: “How can we make water available for all?” Something must be done.
Structure of water
Liquid water
water molecule
water molecule
A water molecule is made up of two hydrogen atoms and one oxygen atom. A single oxygen atom contains six electrons in its outer shell, which can hold a total of eight electrons. When two hydrogen atoms are bound to an oxygen atom, the outer electron shell of oxygen is filled.
The water molecule is composed of two hydrogen atoms, each linked by a single chemical bond to an oxygen atom. Most hydrogen atoms have a nucleus consisting solely of a proton. Two isotopic forms, deuterium and tritium, in which the atomic nuclei also contain one and two neutrons, respectively, are found to a small degree in water.
