Photochemical Smog
.... and volatile organic compounds created from
fossil fuel combustion) interact under the influence of sunlight to produce a
mixture of hundreds of different and hazardous chemicals known as secondary
pollutants. Development of photochemical smog is typically associated with
specific climatic conditions and centers of high population density. Cities
like Los Angeles, New York, Sydney, and Vancouver frequently suffer episodes of
photochemical smog.
One way in which the production of photochemical smog is initiated is through
the photochemical reaction of nitrogen dioxide (NO2) to form ozone. There are
many sources of photoche .....
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UFO's: Seeing Is Believing
.... looking for a more
scientific definition disregard UFO's as nothing more than a mere
misinterpretation of a plane, weather balloon, or meteor. Some have gone
so far as to say that specific witnesses to UFO's have seen nothing more
than a hallucination and "wanted" to see a UFO so their minds adapted that
idea into an illusion to satisfy the urge.
Personally, I have had two encounters with unexplainable objects in
the sky and to disregard them as a misinterpretation or hallucination is an
impossibility. Witnesses who were with me on one of the occasions saw
exactly what I did and we concluded it impossible to be anything but
un .....
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Plutonium
.... after, Seaborg was able to isolate plutonium 239, an isotope used in
atomic bombs.
Plutonium is a highly dangerous and poisonous element because it rapidly
gives off radiation in the form of alpha particles. Alpha particles, which are
identical to the nucleus of a helium atom, consist of two protons and two
neutrons tightly bound together. Although the particles can only travel about
five centimeters in the air, they can cause great damage when the enter the body,
causing cancer and other serious health problems. Beyond the danger of their
radiation, Plutonium will spontaneously explode when a certain amount, call .....
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Quarks
.... protons and neutrons, and can be observed
in ordinary matter. Strange quarks can be observed in omega-minus and other
short lived subatomic particles which play on part in ordinary matter(1985
Quarks).
The interpretation of quarks as physical entities poses two problems.
First, sometimes two or three identical quarks have to be in the same quantum
state which, because they have to have half integral spin, violates Pauli's
exclusion principal. Second, quarks appear to not be able to be separated from
the particles they make up. Although the force holding the quarks together is
strong it is improbable that it could withstand bom .....
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Rates Of Reaction
.... are those particles which are moving,
in the case of magnesium and hydrochloric acid, it is the hydrochloric acid
particles which have to have the activation energy because they are the ones
that are moving and bombarding the magnesium particles to produce magnesium
chloride.
The rate at which all reactions happen are different. An example of a fast
reaction is an explosion, and an example of a slow reaction is rusting. In any
reaction, reactants chemical reactions® products.
We can measure reactions in two ways:
1) Continuous:- Start the experiment and watch it happen; you can use a
computer “logging” system to monitor it. .....
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A Critique Of The Stanford Experiment
.... experiment at
first were thought to be similar in behavior but after one week, all of
that changed. The prisoners became "passive, dependent, and helpless."
The guards on the other hand were the exact opposite. They became
"aggressive and abusive within the prison, insulting and bullying the
prisoners."
After the experiment was finished, many of the mock guards said
that they enjoyed the power. Others said that they had no idea that they
were capable of being so corrupt. The experimenter was shocked at the
results as well saying, "It was degrading....To me, those things are sick.
But they (the prisoners) did everything I said .....
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The Role Catalysts In Chemical Reactions, Their Importance In Industry, Problems And New Developments
.... O-H bond is broken to produce R-O-
and H+. When the reactant receives protons from an acid it undergoes a
conformational change, (change in shape and configuration), and becomes a
reactive intermediate. The intermediate can then either become an isomer by
returning a proton to the catalyst, or it may undergo a further reaction and
form a completely new molecule.
Up until the mid - 1960's silica-alumina gels were used to catalyse the cracking
of hydrocarbons. This form of cracking is where the large molecules in oil are
converted into small, highly volatile molecules. However because the size of the
pores of silica-alumina gels was .....
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The Sequence Of Chemical Reactions
.... 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. Transfer the filter paper into a clean beaker. Add ~ 10
mL of 3M sulfuric acid to the beaker in order to dissolve the filtrate. Remove
and rinse the filter paper. Now add ~ 0.35 g of zinc powder to the solution and
stir until the solution becomes clear. Dissolve the excess zinc with more
sulfuric acid. Decant the liqui .....
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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 semiconductors devices at higher temperatures than germanium.
Now I will give you some brief history of the evolution of electronics
which will help you understand more about semiconductors and the silicon chip.
In the early 1900's before integrated circuits and silicon chips were invented,
computers and radios were made with .....
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Technetium
.... 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 silvery-gray metal that tarnishes slowly in moist air. Until
1960, techne tium was available only in small amounts and the price was as high
as $2800/g. It is now commercially available to holders of O.R.N.L. permits at a
price of $60/g. The chemistry of technetium is said to be similar to that of
rhenium. Technetium dissolves in .....
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Thallium
.... 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 are 3.6 parts of Thallium in every million parts of the Earth’s crust.
Thallium compounds are extremely toxic. The negative effects are cumulative and
can be taken in through the skin. Poisoning from Thallium takes several days to
effect you and when it does, it hits the nervous system. Thallium should only
be handled by tra .....
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Alkanes
.... 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 cleaning fluid. The
Pentanes and Hexanes are also highly flammable and make really cool explosions.
Heptane, octane and nonane make up gasoline. The "Octane Scale" on gas pumps
uses a system which rates n-heptane at a 0 and isooctane at 100.
Currently propane gas is being studied to use it as a fuel for more
efficient cars. He .....
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