14 DAY TRIAL // Just when you think you know everything about it, it starts again acting in unpredictable ways. Water is probably the substance with the longest list of anomalies known to man, meaning it behaves in unique and contrary ways in relation to the vast majority of all the other substances. When it freezes, it expands, as a liquid it's denser than it should be, it has a high melting and boiling point, while when vaporized it's the one of lightest gas known.
Nevertheless, the water is essential to life. Thus, in order to find what makes water so special, chemical engineer Pablo Debenedetti, studying the properties of this substance, found what seems to be a simplified model of a molecule that presents features similar to that of the water. Previously, scientists argued that water is unique due to its behavior and cannot be substituted by any other substance, but Debenedetti proved otherwise.
The computer simulations conducted by Debenedetti mostly involved creating colloidal substances or liquids with small particles in suspension, which have properties similar to that of the water. However, what he has found reveals some discrepancies between theoretical beliefs and realty. One of these is the interaction between water molecules and oil, which do not mix otherwise. While removing the interactions between the atoms which form the water molecules, the chemist realized that the two substances still do not mix.
Generally, this behavior is attributed to the interaction between hydrogen and oxygen atoms. But, two years ago, the same team successfully showed, by simulating colloidal mixtures, that water is not special comparing to any other known substance. Varying the distances between the molecules, they realized they could control the attraction or repelling effect between two different substances, by pressurizing them.
Water is virtually an universal solvent, meaning it dissolves most of the known substances. However, even this feature seems to be odd, its unique chemical composition should not allow this. While studying this particular behavior, scientists simulated interactions between oily materials, and soon showed that even oily solutions present repulsion features between each other when the temperature is being varied over a certain range, regardless the water simulating substance was cooled or heated.
The configuration of the water molecule, is mostly thought to be the origin of these anomalies, as molecules can create bonds in multiple complex ways. The research team decided to ignore this feature, and experimented by varying the distances between particles, until the two substances started repelling each other.
Although the modeled substance has similar behavior to water, Debenedetti stated that they also differ a lot from each other. For example, when the oily substance freezes, it will not form crystals that look like those of the ice, thus it cannot present a scientific value for a "water substitute". Nevertheless, he argues that the next step in his experiment is to recreate it in reality.