Despite its seemingly simple chemical makeup, water has many interesting properties that set it aside from other molecular compounds. It is the catalyst of life, and without it, vital processes could not take place. It is an almost universal solvent, meaning that most substances will dissolve in it, and curiously, when it cools beyond the point of four degrees Celsius, it expands. Yet how could such a simple chemical makeup produce all these wonderful properties? The answer is, it simply doesn’t. Water’s properties come not from its chemical makeup, but from different forces. Quantum effects and intermolecular forces are what govern water’s properties, and there is more to water than is first apparent.

Bonds are what make up a substance’s properties. Hydrogen bonds, the bonds that form between several water molecules when the positive hydrogen atoms are attracted to the oxygen atoms in another molecule. These bonds constantly form and break, and link the molecules in water into a fluid network. When water freezes to make ice, this fluid network turns into a crystal lattice, and is static. Yet curiously, water expands when it freezes. Since heat causes particles to vibrate, Hydrogen bonds are stronger at lower temperatures, since there is less vibration to shake the bonds apart. However, this lattice of pure hydrogen bonds increases the distance between each molecule, reducing the density, and increasing the volume.

That explains the properties of typical H2O, but when you replace the 2 hydrogen atoms in the water molecules with Deuterium, or hydrogen with an extra neutron in its nucleus, you being to see different characteristics. For example, heavy water, water containing deuterium, is poisonous to all but the simplest organisms, and freezes at a higher temperature than the non-heavy type of water. This is because of the uncertainty principle. Because quantum particles need not have a well defined position or momentum, this allows them to get closer together than normal, strengthening hydrogen bonds. In studies done, liquid water containing tritium or deuterium has a 3% shorter bond length, and since bonds are what determine the properties of a substance, this explains why heavy water’s characteristics differ from that of normal water.

Yet the majority of life on earth requires water to survive. Water is the catalyst of life, as many vital processes cannot occur with it. Water is an almost universal solvent, and will dissolve many substances. Bodily fluids consist of substances dissolved in water, and many biochemical reactions will only take place in water. Since water is a polar covalent molecule, its charge enables it to separate polar solute molecules, this explains why water is able to dissolve such a wide range of substances.

In conclusion, water’s properties which distinguish it from other substances come from the bonds that form both within a single molecule, and among several molecules of water. Hydrogen bonds which constantly form and break are key to water’s unique ability to expand when freezing, as well as its uniquely high surface tension, whereas the polar covalent bonds that form between the hydrogen and oxygen atoms are key to its property of being a great solvent.