Did you know that March 22 is World Water Day ? What’s more, did you know that there was a World Water Day? Well, yes, it does exist and that should make us think about the importance of water, not only for us human beings, but also for the rest of the planet and its proper functioning. A curious fact is that planet Earth is the only one of the planets in the Solar System that has liquid water. But there goes another, the fact that there is water on Earth has made it possible for life to develop.
Water has unique physical properties
Water is the only substance on the planet that can be found in three different states in nature at the same time. We can find water in a liquid state as in rivers and seas, in a solid state as in icebergs and in a gaseous state as water vapor and forming part of the atmosphere.
Although traditionally only those three states have been considered, a new state of water, the tunnel state, has recently been discovered . This discovery has been made by a scientific research group of the Department of Energy at Oak Ridge National Laboratory (United States)  . This new state is defined as:
” The oxygen and hydrogen atoms of the water molecule are delocalized and begin to be present simultaneously in all their six symmetric positions at the same time”
This defies the laws of traditional physics and obeying those of quantum physics . This property has been observed in very small spaces, such as the equivalent of one ten billionth of a meter, and it would serve to explain, for example, how water behaves in cell walls. This is undoubtedly one of the most innovative and surprising scientific curiosities about water .
Its molecular structure and the arrangement in space of the hydrogen and oxygen atoms that make it up give it the ability to dissolve many substances. Although it is considered to be the universal solvent , it cannot dissolve all substances, such as oils.
Water is an extremely polar substance (neutral charge) because the distribution of its charges forms a partially negative region (oxygen) and a partially positive region (hydrogen). This polarity allows it to dissolve ions and other polar or charged molecules. When the molecules of another substance come into contact with water they separate into positive and negative charges and the water molecules bind to them based on their charge. If, for example, common salt or sodium chloride is dissolved in water, the negative charges of the water will surround the sodium (positive charge) and the positive charges of the water will surround the chlorine (negative charge). Thanks to this capacity of water, most of the chemical reactions that occur in living beings can occur.
Water is essential for life
Water is essential for the hydration of living beings, it is the medium where many chemical reactions take place and it is also the habitat of many organisms .
In the case of humans, approximately 75% of the brain, 25% of the bones and 83% of the blood is water. Also, a person can live without food for a month or more, but without water they could not survive for more than a week. To maintain good hydration and the proper functioning of the body, you should consume about two liters of water a day, although drinking more than this amount can endanger our health. Drinking water in excess and quickly can reduce the concentration of sodium in the blood and unbalance the percentage of brain water. On the other hand, it helps regulate body temperature and, therefore, it is very necessary to drink water when you have a fever, in the same way, water also regulates the temperature of the planet.
The net amount of water on Earth has not changed in the last thousands of years, and this is mainly due to the hydrological cycle or water cycle . Due to this, it has been estimated that globally, water can remain from 9 to 10 days in the atmosphere as water vapor, from 15 to 32 days in rivers, 17 years in lakes, 300 as groundwater, 3000 years in the ocean and 8,000 to 16,000 years at the poles and glaciers.
Furthermore, it is estimated that there are more than 500 million km 3 of water on the planet. Of that 100%, only 3% is fresh water and the remaining 97% would be equivalent to salt water. Of the total fresh water, 69% is frozen while the rest is distributed among rivers, lakes, wetlands and groundwater. Also, 90% of all fresh water is frozen in Antarctica. However, the total drinking water on the planet is only 0.007% and due to human action and pollution decreases every moment.
Another scientific curiosities about the water you might not know is that e l water is a renewable but limited resource , and yet we need to live and to our economic activities. Unfortunately, not all water is distributed equitably on the planet, and in many cases the poorest areas are also more affected by scarcity and poor water quality. More than 1.1 billion people in the world lack access to safe drinking water, while millions of others need to walk about 10 km a day to get it.
Regarding the quality of the water , it has been estimated that more than 80% of the wastewater that is generated returns to the aquatic ecosystems without any type of treatment. But, the problem goes further, and is that around 1800 million people have to use contaminated water sources putting their health at risk due to the possibility of contracting diseases such as cholera, dysentery, typhus or polio. This lack of quality water causes about 842,000 deaths a year.
Although in many cases the quality of the water could be recovered, in many cases it is not done because it is cheaper. For example, wastewater could be used to recover nutrients and other materials.