The Sequence Of Chemical Reactions
.... solution should be
blue. Bring the beaker back to the lab station and add ~ 10 mL of distilled
water. Stir the mixture, all the while adding ~ 8 mL of 6M of NaOH to the
beaker. Check with litmus paper to ensure that it is slightly basic. Fill the
beaker with up to 100 mL mark with distilled water. Heat the solution and allow
it to boil for 5 minutes. Prepare a squirt bottle with hot water. Filter the
solution and rinse the beaker with the hot water. Rinse the filter cake with
hot distilled water. .....
|
|
Silicon
.... memories, infrared detection and
lenses, light-emitting diodes (LED), photosensors, strain gages, solar cells,
charge transfer devices, radiation detectors and a variety of other devices.
Silicon belongs to the group IV in the periodic table. It is a grey brittle
material with a diamond cubic structure. Silicon is conventionally doped with
Phosphorus, Arsenic and Antimony and Boron, Aluminum, and Gallium acceptors.
The energy gap of silicon is 1.1 eV. This value permits the operation of
silicon semic .....
|
|
Technetium
.... with atomic masses
ranging from 90 to 108, are known. 97Tc has a half-life of 2.6 x 10^6 years.
98Tc has a half-life of 4.2 x 10^6 years. The isomeric isotope 95mTc, with a
half-life of 61 days, is useful for tracer work, as it produces energetic
gamma rays. Technetium metal has been produced in kilogram quantities. The metal
was first prepared by passing hydrogen gas at 1100C over Tc2S7. It is now
conveniently prepared by the reduction of ammonium pertechnetate with hydrogen.
Techne tium is a silv .....
|
|
Thallium
.... many other skin infections. It was then limited
because of the narrow margin between the benefits and its health risks.
Thallium bromide-iodide crystals are still used as infrared detectors. Thallium
sulphate used to be widely used as a pesticide and an ant killer. It was
odorless and tasteless and worked well, but it was found to be too toxic.
Thallium slats which burn with a bright green flame are used in flares and
rockets. Thallium is the 60th most abundant element in the Earth’s crust.
There a .....
|
|
Alkanes
.... periods of time.
As mentioned above chloroform can be produced which can be used for
anesthesia. Also dichloromethane, or paint stripper and 1,2-dichloroethane
which is a dry cleaning fluid. Here is a sample reaction where a halogen
replaces a hydrogen. CH4(g) + C12(g) ----> CH3Cl(g) + HCl(g)
There are many uses for alkanes, for instance: Propane is used in gas
grills, butane is used in cigarette lighters, through various reactions
scientists can make paint stripper, anesthesia or dry cleanin .....
|
|
The Atom
.... the annual Cavendish dinner.
Armed with the electron, and knowing from other experiment that what was
left when electrons were stripped away from an atom was much more massive
remainder that was positively 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 el .....
|
|
The Classification And Formation Of Crystals
.... necessary in the description of each
crystal system.
Isometric
This system comprises crystals with three axes, all perpendicular to one
another and all have equal length.
Tetragonal
This system 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 w .....
|
|
The Comparative Abundance Of The Elements
.... Barium 0.04%, Nitrogen 0.03% and
the rest of the elements on the periodic table take up about 0.5%.
The elements of the crust are graphed below, but only ones that are the
most abundant due to the 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 atmosp .....
|
|
The Effect Of Concentrations Of Starch And Sugar Solutions On Synthetic Semi- Permeable Membranes
.... 5.
Tie a tight knot. Leave the extra string. 6. Insert the transfer pipette (cut
off top) about one third of the way into the tubing. 7. Tie a knot securely
around the transfer pipette. Leave the 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 abou .....
|
|
The Element: Chlorine
.... reacts
directly with many nonmetals such as sulfur, phosphorus, and other
halogens. Chlorine can support combustion; if a candle were to be thrown
into a vessel of chlorine, it would continue to burn, 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 .....
|
|
Greenhouse Effect
.... If this effect were to continue and grow, the earth’s population
would be exposed to serious threats.
Carbon dioxide is essential for plants who use it for photosynthesis, yet too
much can lead to serious 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 atmosph .....
|
|
The History Of Carbon
.... synthetic materials. Diamonds of true gem quality are not
made in this way (Beggott 3-4).
Graphite is another form of carbon. It occurs as a mineral in nature, but it
can be made artificially from 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 bla .....
|
|
The Peregrine Falcon
.... on wildlife, it was
almost too late.
The American peregrine's scientific name is Falco peregrinus anatum.
At one time, people called this falcon a duck hawk. That was a poor name,
since falcons aren't 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 Amer .....
|
|
The Orgins Of Atomic Theory
.... we are.
The Greeks invented science and explored it in its truest form, philosophy.
Through the years we have developed tools that we hope can prove or disprove
various hypothesizes, to further our 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. .....
|
|
The Quicksilver
.... there various ores. Then, once the common metal is extracted
mercury is then separated through distillation.
Without mercury our world would be much different. We would have
different, if any, ways of 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 po .....
|
|
|
|
