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Water and Density
Name: Mtchel W. E.
Status: other
Age: 40s
Location: N/A
Country: N/A
Date: 2000
Question:
As temperature drops the density of water increases until
at about 34 degrees farenheit it reaches its maximum density. as the
temperature falls still further then the density of water then decreases
as it approaches freezing. So you could say that at both around 33
degrees and at 35 degrees the density of water is the same, yet something
is different about those two waters. Is it that the shape of the
molecules at those two temperatures is different but equal in size, or is
something else going on? I am not sure where this leads but I shall tell
you where it took my imagination. I have felt that maybe at those
temperatures the bonds in those molecules can be more easily shifted,
perhaps liberating energy, or perhaps at these low almost freezing
temperatures natural cleavage points are present which would enable
easier seperation into hydrogen and oxygen. so that perhaps by performing
hydrolysis at maximum density at 34 degrees, while lowering the
temperature to 33 drgrees or perhaps even to freezing, would allow the
heat of freezing energy to be somehow used to enhance the hydrolysis with
an energy surplus, or maybe there is a cleavage point at the low
temperature and increaseing density of 33 degrees that allows changing
the shape of the bonds to release energy.
perhaps some experiments could be done in an mri machine using radio waves
to alter the bonds of 33 degree water and 35 degree water and to see if
they can be shifted back and forth with ease. for although 33 and 35
degree waters are not isomers but are maybe just slightly different in
bond positions, it might be enough of a diffeerence that a small change in
the electromagnetic field applied externally chan mutate one water to the
next while skipping the 34 degree maximum density. if 35 degree water
could be shifted instantaneously to 33 degree water with little imput.
in another direction , 34 degree water at maximum density
Replies:
Water is an intensely-studied liquid, yet much about its structure remains
unknown. HOwever, I believe that enough is know to be able to answer your
question. The dip in specific volume of water with temperature is the
result of two competing tendencies: (1) the higher degree of order between
water molecules as the temperature decreases, resulting in a more open,
high-volume (low-density) configuration, and (2) the faster motion of the
water molecules as the temperature increases, forcing the molecules farther
apart. Property (1) is an unusual property of water, arising from its
preferred tetrahedral arrangement of hydrogen bonds. This leads to a solid
(ice) that is less dense than the liquid, which is unlike most other
substances.
The temperature of maximum density simply is the point at which the
contraction due to decreased thermal motion is not outweighed by the
increased order and ice-like structure of liquid water. So although the
average spacing between water molecules at 33 and 35 degrees F are the same,
the relative orientations of the molecules, and their velocities, are
different.
Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois
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Update: June 2012
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