Published in 12 de July de 2018
For professional deformation, when I observe the water, despite its transparency, I always see a photometer of oxygen and hydrogen molecules making it theirs.
70% of our planet is water, but we say “Earth.” We find it everywhere, but above all in the sea (97%). That’s why water is basically saltwater. But there is also something sweet: in the rivers, in the subsoil, in the polar ice caps. At home
We always have it available, opening either a tap or a bottle purchased from the store: we do not know what
It is considered fundamental for the existence of life. There is no known way of life that takes place in its complete absence. We use it for everything. We use so much that we would never be able to say that water is rare. But he is, and very much luckily. Water is a molecule that is composed of an oxygen atom and two of hydrogen (H2O) and has some physicochemical characteristics that make it unique. The behavior of the nature of water and ice is not what it should be, and thanks to this fact – that water is rare – we exist. In solid state it is less dense than in liquid phase and for that reason the ice floats and does not sink. If it were not so, the ice would sink and the cold would freeze the surface water, which would also sink, and we would reach a point where everything would be ice and there would be no water: human beings. In the year 1611, Galileo, as a result of this fact, wrote the Speech on the bodies that float in the water or moved, in which it affirmed that the water was dilated or ruminated. All fluids increase density when cooled, but below
from 4 ° the volume of the water increases and, therefore, its density is reduced.
Water is the only substance that can be found in solid, liquid and gaseous environmental conditions.
Although it is a simple molecule, it has an extremely complex and anomalous nature due to hydrogen bridges, which are the links that unite them. As a gas, it is one of the lightest known; As a liquid, it is much denser than one should expect; As a solid, it is much lighter than it would be compared to its liquid state.
The water boils to 100 °, but if it follows the logic of its companions of the periodic table, it would have to boil below the 80 ° … under zero! The same happens with its freezing point: if it behaves like the rest of its group, it should freeze at about 100 ° under zero! Water is the liquid with the largest surface tension after mercury.
Thanks to this phenomenon, insects can walk quietly over them without sinking and the drops of the dew, sliding through the leaves of the trees. It is an excellent lubricant and at the same time has an unbelievable grip. It skates on it and at the same time it is able to stick with great force (try to put in contact with two sheets of crystalline glass and you will see that it costs much to untie them).
Water is a universal solvent, water … could be writing pages and more pages about its anomalies, though
I’ll end up with one of the most unknown and at the same time more curious and recent: the Mpemba effect, which can be summed up with this question: why does hot water, in certain contexts, freeze before the cold? This effect, which apparently contradicts the psychology, had already been detected by Aristotle more than two thousand years ago, but it was not until recently, in 1969, when a Tanzanian student, Erasto Mpemba, did this ask your teacher a day in class. He explained that a mixture of hot ice cream was frozen before it was cold.
It was from this anecdote that the student and another professor wrote up a technical document about him
theme; a topic that, for the moment, although there are many theories, it still has no consensual response. In fact, in an article published last year seemed to be the “culprits” of this effect being the hydrogen bridge links again.
In summary, then, it can be said, colloquially, that water goes to its own; Luckily.
David Güell, deputy chief of debugging of Aigües de Manresa