Unlike the vast majority of substances, ice floats in water liquids. That's because this is no more dense when you're at 0 ° C, but at 4 ° C. If not, there would be no icebergs or resale pipes to get frost. In addition, rivers and lakes begin to freeze the fund to the surface-and we could not skate on them.It is not the only peculiarity of ice. In fact, there are 14 different varieties, something equally special because solids usually show two or three different types of crystalline structures.
The fact that we all know has a hexagonal structure and is called Ice Ih, but playing with the pressure and temperature can generate other structures.
In nature we also find ice or cubic lc, which is formed from water vapor at normal atmospheric pressure, but at temperatures below 80 ° C below zero. This kind of ice may form in the upper atmosphere.
In 1900, physicist Gus-tav Tammann discovered that the ice if subjected to 3,500 atmospheres-three and a half times the pressure that exists at the bottom of the Mariana Trench-appeared two new states: ice II and III.
A decade later, Percy Bridgman, from Harvard University, identified 5 more varieties. Among them, ice VI was known as "hot ice" since remained without melted to 80 C, provided that they exercise over the 6,500 atmospheres.
Of these, the most ghostly is the ice IV, whose structure was not discovered until 1981, 44 years after being detected, because it becomes very quickly into a more stable, V. And the race continues in 2006, Science magazine reported obtaining ice XIV.
In the solitude of the only space we have found that ice is amorphous. How do you get it? Well, ice cream artisans hold the key: cool very quickly to prevent crystals from forming.
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