Water facts

The human body consists mainly of water. At birth, water even accounts for around 80% of our body. As we get older, however, this proportion decreases, with water accounting for around 60% of adult bodies. In senior citizens, this figure falls to 50%. We need to drink a lot to maintain the water equilibrium of our bodies. Experts suggest drinking at least one and a half litres of water, tea or juice each day.

Whereas all substances generally coalesce in cold conditions and expand with heat, water behaves differently. This is known as the anomaly of water. At around four degrees Celsius, water is at its most dense — that is, it expands the least. However, as soon as it gets colder, freezes and becomes ice, its volume increases. This is due to the spatial structure of the ice crystals. This expansion produces huge forces that can break even the hardest materials. This is why we see frost damage on the asphalt surfaces of our roads or burst pipelines. It’s also not a good idea to refrigerate beer bottles in your freezer compartment! Thankfully, the new nozzles and spray guns of the Original GARDENA System have built-in frost protection.

Around 71% of the Earth’s surface is covered by major oceans. The oceans' total volume is an unimaginable 1.332 billion cubic kilometres. Water is therefore available in abundance. However, 97% of it is salty seawater and therefore only of limited use to humans. Of the remaining 3% of fresh water, around 69% is bound up in glaciers and ice caps. 30% is stored as groundwater in underground reservoirs, some of which are difficult to access. Only around 1% is available as surface water in the form of rivers and lakes.

Scientists believe that only around 0.3% of water on Earth can be tapped as drinking water. The problem is further exacerbated by the fact that fresh water reserves are unevenly distributed around the world. The biggest volumes of non-frozen fresh water are stored in the great lakes of North America. Large desert regions of the world such as the Sahel region or the Gobi desert have very little fresh water and are therefore hostile to life.

From the perspective of chemistry, water is a molecule which consists of to hydrogen (H) and one oxygen (O) atoms each. Thus, it is noted as H20. According to chemical nomenclature it actually should be called dihydrogeniummonoxid or dihydrogeniumoxid. Or according to the standards of the International Union of Pure and Applied Chemistry (IUPAC) also oxidan. Water is the only chemical substance that naturally exists on Earth in liquid (water), solid (ice) as well as in aeriform (steam).