Water Study
"The Amazing Secrets of Water"
Water is both heavier and lighter than any element. Everything floats on it and everything sinks in it. It can clean anything. It ti the worlds strongest solvent. It can break stone, lift mountains. It records information, has a memory and holds your memory... All of this is and more studied in this film. But the end result is that we still know next to nothing about water.
And we abuse it,,,, hmmm....
Watch the film and follow some links. See if you don't start to understand water more, respect it more and begin to appreciate it more.
Download this version [HERE} or email me for free HQ version in avi, mpeg, or any other version.
The New Mystery of Water
(the content from this portion has been
taken from LiveScience's page here..)
Strange Stuff, Water's unique properties:
- The solid form floats on the liquid form. This property also explains why water pipes will burst when they freeze - something opposite of nearly every other simple substance. Mercury thermometers, for instance, do not explode when the temperature drops below the freezing point of mercury.
- The temperatures at which water boils and freezes are both higher than other molecules of similar size.
- Water has a large heat capacity; it can take in a lot of heat without its temperature increasing very much. This makes it an especially good coolant for a car radiator, and it's the main reason temperatures are moderate for coastal communities - as the ocean is slow to cool down or warm up.
- The high surface tension of water - its tendency to fight being pulled apart - explains why it forms droplets and why it climbs up the sides of a straw. It may also play a part in how the water strider walks on water.
A single molecule of water looks like a letter V, with one oxygen atom at the bottom point and two hydrogen atoms at the top. These atoms share some of their negatively charged electrons, forming a strong connection called a covalent bond.
The oxygen atom grabs more of the shared electrons, which makes it slightly negative, leaving the hydrogen ends slightly positive. This small shift in charge is what attracts water molecules to each other.
Saykally describes each water molecule as having hands and feet. The hands are the positively charged hydrogen atoms, while the feet dangle off the negative side of the oxygen.
"Hands can't grab hands and feet can't grab feet," Saykally said, but hands can latch onto feet, in what is called a hydrogen bond.
Hydrogen bonds are 10 times weaker than covalent bonds, but they are the key to water's mysteries.
I only posted a tiny portion of that page. Go [HERE] and read some more, you'll be impressed.
Science & Technology,s View
[This is from the October 5th 2005 Science & Technology article on water.]
WATER would seem to be relatively easy for scientists to understand. It is the only natural substance on Earth that is found as a gas, liquid, and solid. It covers 70 percent of Earth’s surface, makes up 60 percent of the human body, and constitutes 90 percent of a person’s blood.
However, the water molecule is far from simple. Given its low molecular weight, water at ambient conditions should be a gas instead of a liquid. Its boiling point is nearly 200°C higher than expected compared with similar-size molecules. And, unlike most substances, when ice melts, the water molecules pack more closely together than they do when frozen, which is why ice cubes float. In addition to its familiar liquid phase, water has at least 3 other liquidlike phases and up to 14 solid phases.
Water’s unusual properties have unexpected effects on the thermodynamic behavior of its phases. For example, temperature and pressure affect the molecules differently when water approaches its boiling point than when it is close to freezing. Heating already hot water increases its isothermal compressibility and heat capacity and reduces its density, but heating cold water has the opposite effect. Also, applying pressure reduces the mobility of the molecules in hot water but increases their mobility in cold water. Ice melts when slight pressure is applied, but under high pressure, liquid freezes.
Understanding water is important to a range of research areas from geosciences to biological systems to astrophysics. But explaining the anomalous properties of this mysterious molecule has challenged both theorists and experimentalists. Scientists began to simulate liquid water almost 40 years ago. Yet, they continue to pursue more accurate models so they can better analyze this surprisingly complex molecule.
The revolution in supercomputing has been a boon to such research. To simulate even a few hundred atoms requires supercomputing capabilities, such as those available with Livermore’s unclassified supercomputer, Thunder. Funded by the Laboratory’s Multiprogrammatic and Institutional Computing Initiative, Thunder can process 23 trillion operations per second. In June 2005, it ranked seventh on the Top500 List, the leading industry authority for high-performance computing.
By designing algorithms to exploit Thunder’s capabilities, a team of Livermore researchers, led by chemist Christopher Mundy, has made important contributions to the study of water and its properties. With funding from the Laboratory Directed Research and Development Program, Mundy’s team examined the behavior of water at the molecular level under changing conditions. The team’s models reproduced the bulk properties of liquid water. With this improved capability, researchers can better understand the many phases of water and predict the behavior of more complex molecular fluids.
(Great Film, Huh?)
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