posted on 11/19/2020 18:35
(credit: Caesb / Disclosure)
Because it is fundamental to the existence of life, water is one of the elements of nature most studied by scientists. However, despite the plethora of experiments it has undergone, it continues to surprise experts.
In a study published this Thursday (19/11), in the renowned specialized journal Science, an international team of researchers presents evidence that water can exist in two distinct liquid states, a discovery that may explain many of the exotic properties of this liquid so precious.
One of the authors of the article, Nicolas Giovambattista, professor in the Department of Physics at Brooklyn College in the United States, explains that the possibility of water existing in two liquid states had been proposed about 30 years ago, based on computer simulations. .
“This counterintuitive hypothesis has become one of the most important issues in water chemistry and physics. This is because experiments that could access the two liquid states of water were very challenging due to the seemingly inevitable formation of ice at low temperature where water can present, simultaneously, the two liquid states “, explains Giovambattista in a press release.
The common liquid state of water occurs when it is under neither too cold nor too hot, around 25ºC. What the study published in Science showed is that it divides into two liquid states if its temperature drops to around minus 63 ° C and yet, due to other factors, does not freeze. Under these circumstances, it will have a liquid state of high density and another of low density, as if they were two different liquids separated by a very thin layer that joins the two properties.
To reach this conclusion, the team, led by Anders Nilsson, professor of physicochemistry at the University of Stockholm, carried out a series of experiments on a particle accelerator and computer simulations. “We were able to do an x-ray incredibly fast before the water froze and we could see how one liquid turned into another,” describes Nilsson, in a text released by the institution where he works.
The authors believe that confirmation of this property of water – that it can exist in two liquid states simultaneously – should allow for several scientific applications. “There remains an open question as to how the presence of two liquids can affect aqueous solutions in general and, in particular, how two liquids can affect biomolecules in aqueous environments. This discovery will motivate further studies in search of its potential applications”, believes Giovambattista.