Water droplets: surface tension at its finest
This is written for Chemistry or Biology students studying for exams, and people who generally want to know how stuff works. After all, water is an *essential* component of life on Earth; wouldn’t it be interesting to know how it does what it does?
Below is an information-packed video about the Seven Properties of Water. The video may be boring, but watching it will take exactly 1/16th the time that it would take to read a chapter in a gigantic textbook. Also, watching the video will take much less time than reading Wikipedia‘s article on water.
Overview of Water:
Water is made up of zillions of water molecules. Each water molecule is made up of two hydrogen atoms (2H’s) and one oxygen atom (O).
In any given water molecule, electrons — which have negative (-) electronic charges — are more concentrated around the oxygen atom than the two hydrogen atoms. This means that an entire water molecule as a whole has one positive (+) end (“the north pole”) and one negative (-) end (“the south pole”). The hydrogen end is positive (+) and the oxygen end is negative (-).
Since an entire water molecule has two different “poles,” it is termed “polar.” A water molecule’s polarity causes its oxygen atom (-) to be attracted to a hydrogen atom (+) in a different water molecule; opposites do attract. It is in this manner that the oxygen atom (+) of one water molecule is connected to a hydrogen atom (-) of another water molecule. The thing that connects these two water molecules is called a hydrogen bond.
The fact that these special hydrogen bonds connect water molecules to one another — and that hydrogen bonds are weak compared to chemical bonds in other chemical substances — is what makes water unique, and is what gives water its seven properties that help all organisms continue their survival on Earth.
The Seven Properties of Water (and examples of how they affect your everyday life!)
1) Solvent = stuff dissolves into water very easily (e.g., Alka Seltzer tablet dissolving in glass of water)
2) High Specific Heat = it takes a very long time to raise the temperature of water (e.g., a flame raises the temperature of a metal pan much faster than it can raise the temperature of water)
3) Cohesive→&←Adhesive = this is how water defies ↑ gravity! Water molecules stick to one another (Cohesion) and water molecules stick to other, non-water objects (Adhesion) (e.g., water molecules stick to one another and to the inside of a tree in order to move upwards through the tree and deliver nutrients from the soil to its uppermost branches)
4) SurfaceTension = this is why water beads up into water droplets on many objects (e.g., water droplets on a leaf)
5) Variable pH = hydrogen levels are variable due to the weakness of hydrogen bonds, which is why water can be the main ingredient in both coffee (high pH levels = acidic) and bleach (low pH levels = basic)
6) D i s s o c i a t i o n = when water “breaks apart” (e.g., some people believe that the dissociation of water has health benefits because the electric charge of the human body could combine with the opposite charge found in water to create energy)
7) Three Physical States = liquid form (water), solid form (ice), and gas form (steam). These are dictated by the different ways that hydrogen bonds can be connected
– Jonah Lundberg
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