“Water is H2O, hydrogen two parts, oxygen one, but there is also a third thing that makes it water and nobody knows what it is.”—D.H. Lawrence
Chemically, water is simply two atoms of hydrogen joined in covalent bonds to one of oxygen. For something so “simply” made, water is pretty complex; the configuration of its building blocks produces a molecule with unusual and almost magical properties. Water scientists have been disagreeing for the past fifty years over how water molecules arrange themselves in a liquid drop. Below I’ve listed some of the most interesting facts about water:
Water on Earth:
- About 1.5 billion cubic kilometers of water exists on Earth; the equivalent of 1.5 billion trillion litres or 800 trillion Olympic swimming pools.
- The same water that existed on the earth millions of years ago is still present today.
- Water covers about 70 and 75 percent of the earth’s surface.
- Wherever water exists on Earth, life exists; even if that water is nearly boiling, or the area is skin-burningly acidic.
- 97% of the Earth’s water is salty. 2.1% is locked up in polar ice caps and less than 1% is available as fresh water.
- 7% of the fresh water on Earth is trapped in glaciers.
- The human body contains between 60% and 70% water; this changes over a lifetime: a human foetus contains around 95% water for the first months, moving to 77% water at birth; and 70% of the human brain is water. Scientists now believe that on a molecular level, the amount of water in the human body is much higher.
- There is more water in the atmosphere than in all of our rivers combined.
- Ice has covered the Antarctic for over 30 million years. Today, it is covered by 10 thousand trillion tons of snow and ice.
Weird Water Properties:
- Water is sticky. The molecules stick to things, especially each other. This is what gives water its high surface tension and keeps you alive: water can pull blood up narrow vessels in the body, often against the force of gravity.
- Water should be a gas at room temperature—but it isn’t; all similar molecules, such as hydrogen sulphide (H2S) and ammonia (NH3), are gases. This is because water’s stickiness (high water tension) holds molecules together as a liquid.
- Hot water freezes faster than cold water and no one knows why. This phenomenon is known as the Mpemba Effect (named after Erasto Mpemba in 1969).
- There are at least 5 different phases of liquid water and 14 different phases (that scientists have found so far) of ice. See the work by Martin Chaplin (ref below).
- At -120 °C water becomes ultraviscous, or thick like molasses. And below -135 °C, it becomes “glassy water,” a solid with no crystal structure.
- Water exhibits quantum properties such as “coherence” and self-organization.
- Water can dissolve more substances than any other liquid including sulfuric acid.
- Unlike most other liquids, water expands when it freezes. Water expands by 9% on freezing. This has been crucial to life: lakes and rivers freeze from the top down, so even though the Earth has faced successive ice ages, there has always been liquid water for life to continue evolving.
Water in the Universe:
- Water is the second most common molecule in the universe. The most common is hydrogen gas, H2.
- NASA discovered the largest water vapour reservoir around a black hole 12 billion light years from Earth; It contains 140 trillion times as much water as all the water in the Earth’s oceans.
- The sun and other stars like it create the equivalent of 100 million times the water in the Amazon River every second.
- Some form of water was discovered in 23 places in the solar system, including the Moon, Mars, Mercury, Saturn, Neptune and Uranus, Saturn’s and Jupiter’s moons.
- Water arrived on Earth in comets and asteroids some 4.5 to 3.8 billion years ago during a period called the Late Heavy Bombardment.
- An ocean was discovered under the ice crust of Saturn’s moon Enceladus. Since a hydrothermal vent at the bottom of one of the Earth’s oceans is thought to be the best candidate for where life started on our planet, astrobiologists think Enceladus is a good place to look for alien life.
Chaplin, Martin. 2016. “Anomalous Properties of Water”. In: “Water Structure and Science”. Online: http://www1.lsbu.ac.uk/water/water_anomalies.html
Buzzfeed. “27 Fascinating and Strange Facts About Water”. Buzzfeed.com: http://www.buzzfeed.com/tomchivers/fascinating-and-strange-facts-about-water#.yizEKPM8R
Treehugger. “36 Eye-Opening Facts About Water”. Treehugger.com: http://www.treehugger.com/clean-water/36-eye-opening-facts-about-water.html
You can read more information on strange and weird properties of water in my book “Water Is…” available in print and ebook.