The fact that water is a substance that is present almost everywhere, as well as its leading role in the formation and maintenance of most forms of life, we know from the school course. What else can be said about the amazing properties of H2O?
Physics says that one of the main properties is the density of water. We will consider this criterion in more detail. What is this setting? The density of water, like any other substance or material, reflects how much, or, more precisely, what mass is contained in a certain volume of substance.
Why is water so amazing that it is necessary to speak about its density separately? Firstly, this is justified by the number of its species. Water can be fresh and s alty, heavy and superheavy, living and dead. In addition, everyone is familiar with such definitions as ground and mineral waters, rain or melt water, structured and even dry. At the same time, water, as we all remember, can be in a solid, gaseous or liquid state, called the aggregate state. Naturally, the density of s alt water will differ from the densityrainy or frozen.
Explore the characteristics of substances (including the density of water) under normal conditions, which assume an atmospheric pressure of 760 mm Hg. Art. and an ambient temperature equal to 00 C. When these indicators change, the characteristics of substances also change in a certain dependence. Everything but water. The density of water at different temperatures under normal conditions will not be indicative.
Unlike other elements that reduce the density when heated, water in the range from 0 to 4 degrees Celsius increases its density. When cooled, the volume and density of water again behave uncharacteristically: its volume increases, and its density decreases. This is exactly what can be observed in a situation where frozen water breaks water pipes. In wildlife, an unusual feature of H2O protects the lower layers of water bodies from freezing and keeps their inhabitants alive. As for the increase in water temperature, after the limit of 40 C, its density, as with cooling, begins to fall. Sea water also breaks these ideas, showing the maximum density at sub-zero temperatures.
It is surprising that perfectly clean water, without air bubbles and microscopic inclusions of dirt or dust present in it, can be cooled to -70 degrees, without ice formation, or heated without boiling to a temperature limit of 150 degrees Celsius. Suchanomalies are possible under certain conditions (increased pressure, for example), and their reproduction is possible only in laboratory conditions.
In general, the density of water is affected by the presence of impurities, gas bubbles and s alts in its composition, the value of atmospheric pressure, ambient temperature and a number of other external factors. This simple substance never ceases to amaze scientists with its absolutely fantastic physical properties, the ability to change its structure and chemical composition.
