Water has the chemical formula H2O, composed of two hydrogen atoms and one oxygen atom. It is often referred to in science as the universal solvent. Water is the only pure substance found naturally in all three states of matter: solid; liquid and gas.
Water may take many forms; the solid state of water is commonly known as ice or amorphous solid water; the gaseous state is known as water vapour or steam; and the common liquid phase is generally called: simply, water.
Water goes by many names: hydroxic acid, H20. The clear liquid can sometimes act as an acid in a chemical reaction, giving it the term hydroxic acid.
An important feature of water is its polar nature. The water molecule forms an angle, with hydrogen atoms at the tips and oxygen at the vertex. Since oxygen has a higher electronegativity than hydrogen, the side of the molecule with the oxygen atom has a partial negative charge. A molecule with such a charge difference is called a dipole. The charge differences cause water molecules to be attracted to each other and to other polar molecules. This attraction is known as hydrogen bonding, and explains many of the properties of water.
Hydrogen bonding also gives water its unusual behavior when freezing. When cooled to near freezing point, the presence of hydrogen bonds means that the molecules, as they rearrange to minimize their energy, form the hexagonal crystal structure of ice that is actually of lower density: hence the solid form, ice, will float in water. In other words, water expands as it freezes, whereas virtually all other materials shrink on solidification.
The human body it’s just water, the substance we drink, shower with or swim in. As summer is winding down, it may get cooler. But as you’re walking around campus, it’s important to remember that you still need your water. The human body is estimated to be about 60 to 70 percent water. And, if you don’t replenish that water, it won’t replenish itself.