Nonmetal Silicon The second most abundant element on Earth is the nonmetal
silicon, which makes up about 28 percent of the Earth's crust. It
occurs only in such combined forms as silica (silicon dioxide) and
silicate rocks and minerals. The most common form of silica is quartz,
which includes sand and flint. Silicates are salts in which silica is
combined with oxygen and other elements, such as aluminum, magnesium,
calcium, sodium, iron, and potassium.
Silicon has a strong affinity for oxygen. Pure silicon can be obtained
by breaking down its combined form. It is prepared commercially by
reducing (removing the oxygen from) the oxide by reaction with a
carbon-based substance such as coke in electric furnaces. Some silicon
is obtained by reducing silicon dioxide with aluminum. Amorphous
silicon, prepared in the laboratory by heating silica with magnesium
powder, is a dark-brown crystalline powder.
Pure silicon is a hard, dark-gray solid with a metallic luster. Its
crystalline structure is the same as that of the diamond form of
carbon, with which silicon shares many chemical and physical
properties. Elemental silicon has few applications; it is used in
metallurgy as a reducing agent and as an alloying element in steel,
brass, and bronze. (See also Alloy.)
Highly purified silicon is a poor conductor of electricity. When it is
doped, or treated with other atoms, however, it yields electrons for a
current. The silicon that is produced in this process is used
extensively in transistors, integrated circuits, photoelectric
devices, and othe...
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...20? C) 5.75-7.31
Boiling Point 4,118? F (2,270? C)
Melting Point 450? F (232? C)
Germanium, brittle silver element predicted in 1871 by Mendeleev but
not discovered until 1886 by Clemens Winkler. It is used as
superconductor in electronics; window and lens component in equipment
to measure infrared radiation; component of camera lenses and
microscopes; and in transistors and in phosphors for fluorescent
lamps. It is found as a part of the minerals argyrodite, germanite,
and renierite and in coal. It can kill certain harmful bacteria
without causing toxicity to humans and is being studied as a
therapeutic agent.
Properties of Germanium
Symbol Ge Atomic number 32 Atomic weight 72.59 Group in periodic table
IVa Boiling point 4,892o F (2,700o C) Melting point 1,719o F (937.2o
C) Specific gravity 5.323
The physical properties of sulfur are a bright yellow powder. When it is burned you will see a clear blue flame and it has a strong odor. Sulfur has a melting point of 239.38 degrees Fahrenheit, a boiling point of 832.28 degrees Fahrenheit, and the density is 2.67 g/cm. Sulfur has sixteen electrons, protons, and neutrons. When sulfur reacts with the air it produces a gaseous dioxide. It does not react with water under normal circumstances. Sulfur reacts with halogens when it is heated. Sulfur makes up almost 3 percent of the Earth’s mass. At
Silvery white and soft enough to be cut with a knife, gallium takes on a
Upon reading the first page, I knew I would like this book. The writing style is almost like a memoir; it’s in the first person from the perspective of Nomi Nickel. The first ten chapters give us a look into Nomi nickels past, her opinions, and thoughts. They show the transition of her thoughts from a straight edge Mennonite follower to a rebellious teenager. She has a dry sense of humor that is thrown into her everyday activities. It’s a surprise when it happens, like when the garbage men throw out Ray’s hutch, not only was that unexpected but Ray’s reaction was surprising. Many of the teens in the town represent a character foil. On Saturday nights they go out drinking, partying, having sex, and on Sunday they return to their strict religious
There is big deal of interest in silicon carbide (SiC) as an electronic material for high-voltage, high-power and high temperature applications. In this thesis, characteristics of Double gate vertical metal semiconductor field effect transistors (MESFET) fabricated on N/N+ 3C-SiC grown on N+ Si substrate are reported. The most intriguing electronic property of silicon carbide is that it is the only semiconductor material other than silicon that can have electronically passivated surface to industrial standards. The surface passivation is the main reason for the dominance of silicon but, in addition to that, silicon carbide has superior bulk properties. This combination of factors raises the question whether silicon carbide can play a role in main stream electronics (integrated-circuit based complex systems). After analysis of both technical and commercial factors and challenges leads to a conclusion that developing a silicon-carbide film on silicon wafers is the most promising way for silicon carbide enter the mainstream electronics. SiC MESFET shows great promise in high power/temperature operations when compared to Si counter parts. The simulations were performed on ATLAS (SILVACO) software, and results are presented.
M. Salib, L. Liao, R. Jones, M. Morse, A. Liu, D. Samara-Rubio, D. Alduino, and M. Paniccia, “Silicon Photonics,” Intel Technol. J., vol. 8, p. 143, 2004.
However, it can also be located in the in the bulk of the silicon both
Calcium is a solid, with a melting point of 〖842〗^0C. The boiling point of Calcium is 〖1484〗^0C. It is a shiny, soft substance. The estimated crustal abundance of Calcium is 4.15*〖10〗^4milligrams per kilogram. The estimated oceanic abundance of Calcium is4.12*〖10〗^2. This metal can be used to remove oxygen, sulphur, and carbon from certain alloys. Since calcium has a high reactivity with common materials it is rarely used as a metal. Calcium metal is used as a reducing agent in preparing other metals such as thorium and uranium. Calcium is also used in a compound mixture of calcium carbonate; used as a building material (limestone).
Boron is an element that is resistant to heat. And ha another form called crystalline form and that is when
PostText1: Annealing allows plastic to "bend" like the proverbial willow tree, instead of breaking like the proverbial oak.
When an element is teratogenic it disturbs the process of how a fetus or embryo develops. It is known that workers who come in contact with small doses of the element through the air obtain “Tellurium breath” which as a result develops an odor similar to garlic. The main use of Tellurium is to enhance the machinability of alloys like copper and stainless steel. It can also be used with semiconductors involving copper, gold, silver, and tin. If you add Tellurium to lead it can increase its hardness and strength as well as improve its resiliency to acids. Tellurium also has applications in oil refining, solar cells, CDs and DVDs, tinting ceramics and glass, as well as improving the qualities of rubber. If the world was to run out of tellurium a replacement would need to be found quickly due to the uses of it. Tellurium is used to make thin, cheap solar panels. Without another alternative the price of solar panels would increase due to the cost of more expensive materials. But new processes have allowed for photovoltaic cells and circuit boards can be recycled and broken down for
Capitalist. (2012, February 1). Rare Earth Elements - The Technology Metals (Infographic) | Visual Capitalist. Visual Capitalist. Retrieved October 27, 2013, from http://www.visualcapitalist.com/portfolio/rare-earth-elements-the-technology-metals-infographic
BACKGROUND Types of Silica Crystalline silica may be of several distinct types. Quartz, a form of silica and the most common mineral in the earth's crust, is associated with many types of rock. Other types of silica include cristobalite and tridymite. Potential for Exposure During Construction Concrete and masonry products contain silica, sand and rock containing silica. Since these products are primary materials for construction, construction workers may be easily exposed to respirable crystalline silica during activities such as the following: Chipping, hammering, and drilling of rock Crushing, loading, hauling, and dumping of rock   high dust concentrations.
German Chemist Hans von Pechmann first synthesized Polyethylene by accident in 1898 by heating diazomethane. His colleagues characterized the waxy substance polyethylene due to the fact that they recognized that it consisted of long ethene chains. It was then first industrially synthesized by accident in 1933 by applying extremely high pressure to ethylene and benzaldehyde. Over the years, development of polyethylene has increased due to the additions of catalyst. This makes ethylene polymerization possible at lower temperatures and pressures.1
Cerium was found for the first time in both Sweden and Germany in the same year. Today, it is usually obtained by an ion exchange process from monazite sand, which is known to have many rare earth elements inside. Cerium is dangerous by itself but can be used to make carbon arc lights for studio lighting in the motion picture industry. Misch metal has many metals in it, including cerium, and is used to make flints for lighters. Cerium oxide (Ce2O3 and CeO2) is used in self-cleaning ovens, gas mantles and to polish glass surfaces. Cerium does not have any major medical uses but, can have minor ones, like in the polish used to polish glass after cleaning. In 2012, to buy a kilogram of cerium oxide it is about $26. The price fluctuates quite a lot, for example, in September of 2011 a kilogram of cerium oxide was $118. Cerium is a conductor with a low density of 6.689 grams per cubic centimeters. The melting point is 1071o K, which is about 1468.13o F and the boiling point is 3697o K, which is 6194.93o