MERCURY
Mercury is a metallic element that is a liquid at room temperature, it is one of the transition elements. Mercury's atomic number is 80. It is superconductive when cooled to within a few degrees of absolute zero. Mercury was once known as liquid silver or quicksilver which was studied by the alchemists. Mercury was first distinguished as an element by the French chemist Antoine Laurent Lavoisier in his experiment on the composition of air. At room temperature mercury is a shining, moving liquid that has a silvery-white color, and slightly volatile. Mercury remains a liquid over a wide temperature range. Mercury is a solid when given a pressure of 7640 atmospheres (5.8 million torrs). It dissolves in nitric or concentrated sulfuric acid but is resistant to alkalies. Mercury melts at -39C, boils at about 357C,and has a gravity of 13.5. The atomic weight of mercury is 200.59. Mercury comes in its pure form or combined with silver in small amounts. It is mostly found in the form of the sulfide.
Mercury has many uses and is a very important element. A major use of mercury is in electrical equipment such as fluorescent lamps, and mercury batteries. Mercury is used in thermometers because the change in volume for each degree of rise or fall in temperature is the same. The use of mercury in the thermometer instead of alcohol was done by Gabriel Daniel Fahrenheit in 1714. It was also used in vacuum pumps, barometers, and electric rectifiers and switches. Mercury is used in a mercury-vapor lamps which are used as a source of ultraviolet rays in homes and for sterilizing water. Mercury-vapor is also used instead of steam in the boilers of some turbine engines. Mercury is sometimes used for amalgamation. Amalgamation is a metallurgical process that utilizes mercury to dissolve silver or gold to form an amalgam. This process has been largely supplanted by the cyanide process, in which gold or silver is dissolved in solutions of sodium or potassium cyanide.
Mercury is a poisonous element. Mercury is semi hazardous as a vapor and Among the many good things mercury does for people there is a flip side. in the form of its water-soluble salts. Chronic mercury poisoning, which occurs when small amounts of the metal are repeatedly ingested over long periods of time, causes irreversible brain, liver, and kidney damage.
Tuesday, January 1, 2013
Following a dream toward freedom
"Following a dream toward freedom"
465 words
"Following a dream toward freedom"
Freedom has always come very easily for
me. I've always had it and I've never been
without it. But as I sit here thinking I remember
all the stories that were told to me, about the
struggles we were put through to get these
freedoms. Since I am a black woman my
general knowledge of history tells me that
the struggle for freedom was extremely
great. Blacks had to endure slavery and go
through wars to achieve their freedoms.
Woman had to live in silence while the world
was run without their say. To overcome this
they created woman's suffrage and woman's
rights acts to finally allow them their
freedoms. It is an extremely triumphant feeling
to know the things they went through to give
me the luxuries I have today. But what if they
didn't? What if we were still having to fight
wars for our freedoms? I often wonder what
slavery would be like? Looking in todays
society slavery is still the same nightmare it
was then. People in South Africa and Iran
wake to this same nightmare everyday. They
have no personal rights or freedoms at all.
Everyday they live in fear for their lives. If its
not being threatened by their own government
its being threatened by the lack of food they
receive. Imagining the things they go through
everday makes me wonder about my freedoms.
Why is it that I can go to my refrigerator
whenever I want and be able to get a nice,
clean drink of water. When Meanwhile in some
foreign country some 10 year old kid, who has
the same thirst as I do has to go to a lake
where the animals bathe to get a foul, disease
infested drink. Knowing about these peoples
sufferings really makes me realize how
important and how special the freedoms that
Americans posses are. I believe everyone takes
their freedoms for granted. We are by far
granted the greatest freedoms in the
world.But we are far from perfect and
unfortunately we have our own struggles for
freedom. Ranging from racial freedoms to
religious freedoms. I believe that freedom is
the greatest thing in the world but
unfortunately there are a lot of sacrifices to
be made. Americans need to realize that
freedom is not a necessity. We don't have to
have it. Freedom is a gift. It is the most precious
gift in the world simply because it cannot be
bought in any store. It is given to you just for
being an American. My last thought on this is
that I think everyone has had and still has
there struggles with freedom. But I believe
that what doesn't kill us makes us stronger,
so the struggles we endure are worth it in the
end........Aren't they?
465 words
"Following a dream toward freedom"
Freedom has always come very easily for
me. I've always had it and I've never been
without it. But as I sit here thinking I remember
all the stories that were told to me, about the
struggles we were put through to get these
freedoms. Since I am a black woman my
general knowledge of history tells me that
the struggle for freedom was extremely
great. Blacks had to endure slavery and go
through wars to achieve their freedoms.
Woman had to live in silence while the world
was run without their say. To overcome this
they created woman's suffrage and woman's
rights acts to finally allow them their
freedoms. It is an extremely triumphant feeling
to know the things they went through to give
me the luxuries I have today. But what if they
didn't? What if we were still having to fight
wars for our freedoms? I often wonder what
slavery would be like? Looking in todays
society slavery is still the same nightmare it
was then. People in South Africa and Iran
wake to this same nightmare everyday. They
have no personal rights or freedoms at all.
Everyday they live in fear for their lives. If its
not being threatened by their own government
its being threatened by the lack of food they
receive. Imagining the things they go through
everday makes me wonder about my freedoms.
Why is it that I can go to my refrigerator
whenever I want and be able to get a nice,
clean drink of water. When Meanwhile in some
foreign country some 10 year old kid, who has
the same thirst as I do has to go to a lake
where the animals bathe to get a foul, disease
infested drink. Knowing about these peoples
sufferings really makes me realize how
important and how special the freedoms that
Americans posses are. I believe everyone takes
their freedoms for granted. We are by far
granted the greatest freedoms in the
world.But we are far from perfect and
unfortunately we have our own struggles for
freedom. Ranging from racial freedoms to
religious freedoms. I believe that freedom is
the greatest thing in the world but
unfortunately there are a lot of sacrifices to
be made. Americans need to realize that
freedom is not a necessity. We don't have to
have it. Freedom is a gift. It is the most precious
gift in the world simply because it cannot be
bought in any store. It is given to you just for
being an American. My last thought on this is
that I think everyone has had and still has
there struggles with freedom. But I believe
that what doesn't kill us makes us stronger,
so the struggles we endure are worth it in the
end........Aren't they?
Flight Chemistry
Jonathan Cerreta
Chemistry
"Crash Course in Density"
As flight 143, a twin engine 767, was passing over Red Lake on its was to Edmonton, Canada, the left front fuel pump warning light went on. There were a few possibilities for this to happen, such as the fuel pump failing, a fuel line clogging, or a empty fuel tank. The former two were easily dealt with, since the plane could fly without one fuel pump. However, the last possibility was horrifying. After a few minutes, the second fuel pump in the left wing began to blare. It would be too much of a coincidence for two fuel pumps to independently fail, or two fuel lines to independently clog, so it was apparent that the left tank was out of fuel.
Quickly, the pilots decided that getting to Edmonton was out of the question. The nearest large airport was at Winnipeg, so they radioed ahead and changed their course. In a few minutes, all four of the fuel pumps had failed. The worst possible news, they were out of fuel. In a few more minutes the engines stopped running, and all of the high tech instruments became useless.
They realized that they could not even make it to Winnipeg. Their only chance was an abandoned to a abandoned Air Force airstrip. Unfortunately, the airstrip had been converted to a race track, complete with race cars, fences, and spectators. The 767 crash landed, and, fortunately, no one was killed.
Their were many contributing factors that made this plane run out of fuel. First of all, the computerized fuel gauge was not working, and a maintenance worker said , incorrectly, that the plane was still certified to fly. To measure the amount of fuel remaining, they use a drip stick method. They discovered that their was 7 682 liters in the tank. However, they had always measured fuel in the past as pound, while the 767 consumed fuel in kilograms. The drip sticks did not express the amount of fuel in pounds or kilograms, but in liters. It seems to be a simple matter of conversion to arrive a the answer. All they needed to know was how many kilograms were in a liter. Someone said 1.77, and they calculated the value they needed. However, the conversion of 1.77 was not Kilograms per liter, but pounds per liter. The actual value it .803. They were off by more than 50%. This problem would have been avoided if they had kept track of the units during the conversion. That is why it is always important to keep track of the units.
Chemistry
"Crash Course in Density"
As flight 143, a twin engine 767, was passing over Red Lake on its was to Edmonton, Canada, the left front fuel pump warning light went on. There were a few possibilities for this to happen, such as the fuel pump failing, a fuel line clogging, or a empty fuel tank. The former two were easily dealt with, since the plane could fly without one fuel pump. However, the last possibility was horrifying. After a few minutes, the second fuel pump in the left wing began to blare. It would be too much of a coincidence for two fuel pumps to independently fail, or two fuel lines to independently clog, so it was apparent that the left tank was out of fuel.
Quickly, the pilots decided that getting to Edmonton was out of the question. The nearest large airport was at Winnipeg, so they radioed ahead and changed their course. In a few minutes, all four of the fuel pumps had failed. The worst possible news, they were out of fuel. In a few more minutes the engines stopped running, and all of the high tech instruments became useless.
They realized that they could not even make it to Winnipeg. Their only chance was an abandoned to a abandoned Air Force airstrip. Unfortunately, the airstrip had been converted to a race track, complete with race cars, fences, and spectators. The 767 crash landed, and, fortunately, no one was killed.
Their were many contributing factors that made this plane run out of fuel. First of all, the computerized fuel gauge was not working, and a maintenance worker said , incorrectly, that the plane was still certified to fly. To measure the amount of fuel remaining, they use a drip stick method. They discovered that their was 7 682 liters in the tank. However, they had always measured fuel in the past as pound, while the 767 consumed fuel in kilograms. The drip sticks did not express the amount of fuel in pounds or kilograms, but in liters. It seems to be a simple matter of conversion to arrive a the answer. All they needed to know was how many kilograms were in a liter. Someone said 1.77, and they calculated the value they needed. However, the conversion of 1.77 was not Kilograms per liter, but pounds per liter. The actual value it .803. They were off by more than 50%. This problem would have been avoided if they had kept track of the units during the conversion. That is why it is always important to keep track of the units.
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