5 Scientific Knowledge About Water
Water, which occupies 70% of the earth's surface area, is an indispensable resource for all living things, including humans. Richard Seikary, a professor of chemistry at the University of California, Berkeley, explains five such tips on water.
Five Things We Still Don't Know About Water—Richard Saykally Takes Us Inside Waters' Mysteries
◆ 1: There are two types of liquid water
By condensing water vapor on a cryogenic substrate, amorphous ice is produced, which has a high viscosity unlike ordinary water and is close to crystals but undergoes a diffusion phenomenon peculiar to liquids. It is said that it has been observed by experiments that water has two types of molecular structures in this way, but the process of its formation is being discussed.
◆ 2: How many types of ice are there?
According to the latest information, it is known that there are a total of 17 types of ice crystal systems. However, 15 of these were experimentally obtained, and it is said that there are two types of naturally occurring ice crystals: the normal ice Ih phase and the ice Ic phase that may be present in the upper atmosphere. Mr. explains. When ice is produced in the laboratory, when pressure is applied, the low-density solid morphology may collapse into various structures until the close-packed limit is reached, which produces 15 types of crystalline ice. ..
◆ 3: How does water evaporate?
Evaporation rate of liquid water is one of the uncertain issues in modern climate modeling, Saikaly said. The evaporation rate is expressed by multiplying the collision rate between molecules by a coefficient called the evaporation coefficient, but the value of the evaporation coefficient has fluctuated greatly in decades of research, and the exact value can be specified. He said he didn't. Therefore, the exact mechanism of how water evaporates has not been fully analyzed.
◆ 4: Is liquid water acidic or basic?
Since each droplet behaves as if it were negatively charged, it has long been considered evidence of the accumulation of negative hydroxide ions on the surface of the droplet. However, recent experiments have suggested that filling the water surface with hydrogen ions produces an acidic, positively charged surface rather than a basic negatively charged one. Saikaly explains that neither can be said because of the combination of various factors.
◆ 5: The nature of water trapped in a nano-sized space
When water is taken into a hydrophobic space with a size of about 1 nanometer (one billionth of a meter), water molecules show a phenomenon of delocalization and the boundary between the state of water and ice becomes unclear. .. It is said that this state, which is significantly different from normal water, may affect everything from living cells to geological structure, but its characteristics are still ambiguous, and it is said that much research needs to be done in the future. Mr. says.
Related Posts:
in Science, Posted by log1p_kr