The Atom
.... charged, Thomson went on in the next decade to
develop a model of the atom that came to be called the "plum pudding" model.
The Thomson atom, "a number of negatively electrified corpuscles enclosed in a
sphere of uniform positive electrification" like raisins in a pudding, was a
hybrid: particulate electrons and diffuse remainder. It served the useful
purpose of demonstrating mathematically that electrons could be arranged in a
stable configurations within an atom and that the mathematically stable
arrangements could account for the similarities and regularities among chemical
elements that the periodic table of the eleme .....
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The Classification And Formation Of Crystals
.... comprises crystals with three axes, all perpendicular to one
another; but only two are equal in length.
Orthorhombic
This system comprises crystals with three mutually perpendicular axes,
all of different lengths.
Monoclinic
This system comprises crystals with three axes, all unequal in length,
two o which are not perpendicular to another, but both of which are
perpendicular to the third.
Triclinic
This system comprises crystals with three axes, all unequal in length
and is not perpendicular to one another.
Hexagonal
This system comprises crystals with four axes. Three of these axes are
in a single plane, proportiona .....
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The Comparative Abundance Of The Elements
.... fact that the abundance of the other elements of the
crust are too low to graph accurately on one graph.
Almost all elements are found as compounds, however Oxygen, Nitrogen,
and to a lesser extent sulfur, gold, silver and platinum are the only elements
which can be found in almost there raw sate. The atmosphere contains Oxygen and
nitrogen, but it only contains a small portion of the earth's oxygen, this is
because most of the world's oxygen is found in water, oxides of metals, and as
silicates. Common soils and clays are silicates.
2. Living Things
In living things (plants, animals, people) the six most abundant element .....
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The Effect Of Concentrations Of Starch And Sugar Solutions On Synthetic Semi- Permeable Membranes
.... extra string. 8. Add two transfer
pipettes (two squirts) of the Gatorade solution to the tubing. 9. Add two
transfer pipettes (two squirts) of the starch solution to the tubing. 10. If you
spilled any solutions while transferring, carefully rinse the tubing. 11. Fill
the cylinder with distilled water to about 2.54 cm from the top. 12. Place the
tubing into the cylinder of water. 13. Rest the apparatus against the ring stand.
14. Note the height of the water in the tube. 15. Record the time the tube was
placed into the cylinder (it will stay for about 20 minutes)
Time tubing was placed into cylinder: 1:15.00 p.m.
Time tubing was .....
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The Element: Chlorine
.... releasing dense,
black clouds of smoke, The chlorine combines with hydrogen of the
paraffin, forming hydrogen chloride, and uncombined carbon is left in
the form of soot. Soot is black residue from fuel. Chlorine replaces
iodine and bromine from their salts. Dry chlorine is somewhat inert or
not able to move, but moist chlorine unites directly with most of the
elements.
History
Chlorine was discovered in 1774 by Karl Scheele. Humphry Davy
proved that chlorine was an element. Extensive production began 100
years later. During the 20th Century. The amount of Chlorine used was
considered a measure of industrial growth. In, 19 .....
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Greenhouse Effect
.... threats. The problem lies in the disruption of the
balance between how much carbon dioxide plants intake, and what our population
produces. If this natural filtering process is unbalanced, the atmosphere will
receive too much carbon dioxide and other greenhouse gases. Once these gases
form in the atmosphere, they act as barriers trapping in heat and warming the
earth.
This process is not new. In fact, without the greenhouse effect, the average
surface temperature of the earth would be about 59 Fahrenheit degrees lower than
it is today. "Long before civilization intervened , the thin blanket of gases
that surround the earth w .....
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The History Of Carbon
.... amorphous carbon. One of the main uses for
graphite is for its lubricating qualities. Another is for the "lead" in pencils.
Graphite is used as a heat resistant material and an electricity conductor. It
is also used in nuclear reactors as a lubricator (Kinoshita 119-127).
Amorphous carbon is a deep black powder that occurs in nature as a component of
coal. It may be obtained artificially from almost any organic substance by
heating the substance to very high temperatures without air. Using this method,
coke is produced from coal, and charcoal is produced from wood. Amorphous
carbon is the most reactive form of carbon. Be .....
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The Peregrine Falcon
.... hawks and they rarely kill ducks. The American
peregrine was once found all across the eastern United States and southern
Canada. In the west, the species was found from Mexico to California. DDT
poisoning hit this subspecies the hardest. Even today, naturalists are
still working hard to save the American peregrine from extinction.
The smaller tundra peregrine (Falco peregrinus tundrius) lives
farther north. Tundra peregrines range across the treeless regions of
Alaska and Canada. They are also found in Greenland. Peale's peregrine
(Falco peregrinus pealei) is the third North American subspecies. This
western bird ran .....
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The Orgins Of Atomic Theory
.... understanding of any number of things. We
divide science into categories and then sub-divide it even farther, until we can
hide the connections and pretend that they really are separate. The difference
between psychology and physics is not as extreme as one would believe if they
were to read their definitions. Though the means are different the goal is the
same for all science: to increase our understanding of our earthly domain, and
to improve ourselves. The Greeks created this guiding principle more than two
thousand years ago.
Greek atomic theory was not the work of a single person, in fact it was a
product of many great minds. .....
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The Quicksilver
.... determining temperature. Mercury is also used in
cleaning modern day swimming pools as "Mercury Vapor lamps" for sterilization.
Mercury can be used in both reconstructing and destroying life in water ways
depending upon the attention people give it. We would have no fast, economical
ways of cleaning large pools; no fast, economical way of controlling river
clean-ups. Life in our modern day households would be much, much colder because
we would have no way of having a auto-start heater- people would have to turn on
their heater manually. Yet we would also need to look at the positive side of no
mercury. We would have little, if an .....
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Through A Narrow Chink: An Ethical Dilemma
.... the great
tragedy of most scientific discovery, since I firmly believe each scientist is
responsible for that which he creates.
Djerassi does confront a few questions of ethics and morality after the
fact.
On page 61, in chapter 6, he reflects on the argument of the use of poor
Mexican and Puertorrican women for preliminary experiments. Is this just
another manifestation of exploitation of the poor?
Djerassi says absolutely not.
Yes, the poor our the initial guinea pigs for research but this is no
different from what dentists, barbers, and young surgeons do. All of these
groups use the poor to hone their skills, not beca .....
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Tin
.... such things as electical contacts.
Tin is also used as a protective coating. This protective coating can be as
small as 15/1,000,000 of an inch. This protective coating protects against rust
on steel and other metals. A coating of tin also gives a great look to plain old
steel.
Tin cans for food prevents weak acids from damaging the inside of the can.
Not many cans are made of tin since aluminum started to be used for cans tins
use dropped sharply.
Tin is also used to coat staples, pins, bronze bell, pewter pitchers and many
others things.
Another popular tin mixture is tin and lead. Tin and lead make solder for
el .....
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