Even though the International Convention on the Rights of the Child was adopted on 20 November 1989, it was preceded by the Universal Declaration of Human Rights, whose 60th anniversary was celebrated on 10 December 2008 by the UN, a prestigious partner of CyberDodo.
CyberDodo and Water (1-32)
Water is a precious resource, in fact, contrary to appearances, this resource that is so precious to man is very rare. Let's find out together about this vital and much coveted resource, water.
70% of the surface of our planet is covered in water, but take note, 97% of this water is salty, which means that the amount of fresh water only constitutes a paltry 3 percent, of which 2% is ice (the Poles, glaciers, etc ).
There is therefore only one percent available for human consumption or irrigation (The watering of crops furthermore uses up 2 thirds of this fresh water), so it is absolutely necessary to preserve this resource, which should become the inalienable property of all.
What is water?
Water is a molecule formed from one atom of oxygen (O) combined with two atoms of hydrogen (H for Hydrogen and 2 for two atoms = H2), in chemical language water is known as H2O, but it also has other names such as hydrogen oxide or even hydroxic acid.
In terms of temperature, water molecules have greater or lesser activity, the lower the temperature, the lesser the movement (Until it changes into ice), on the other hand, the higher the temperature, the greater the movement (It's almost steam in this state).
Water in all its states: liquid, gas and solid!
Water is in a liquid state when the atmospheric pressure temperature (Sea level) is normal .
When the temperature of water in its liquid state is reduced, the movement of the molecules slows down so that little by little they become hard and change into ice. At normal atmospheric pressure, ice is formed at less than 0 degrees Celsius.
The gaseous state of water is called steam, it is produced when water is heated up and the temperature is very high. To get water in a gaseous state (at normal atmospheric pressure), a temperature equal to or higher than 100 degrees Celsius is necessary. When heated up, the molecules move very fast, so that the steam takes up all the space that is available. As with any other gas, one can say that it is expansible. On the other hand, it is also possible to reduce the amount of space and compress steam.
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