Metalloid

Metalloid (also known as a semimetal) are a group of chemical elements with physical properties that lie between those of metals and nonmetals. Silicon is the most common metalloid. It is silvery and somewhat shiny but brittle, not flexible like most metals. These elements mark the line between true nonmetals and metals.

List of metalloids

 * Boron[[Image:BoronSample.jpg|thumb|Crystal Boron.]]
 * SiliconSILICON.jpg
 * Germanium
 * Arsenic
 * Antimony
 * Tellurium
 * Polonium

Location
Most elements on the periodic table fit into one of several families. Each family having elements with similar characteristics. There is a line that divides the nonmetal families from the metallic families. On either side of the line, seven of these elements are metalloids. These semi, or half metals, form the stair step line between the two types of elements. The line is often called the amphoteric line. These elements are contained in groups: 13, 14, 15, 16, and 17 on the table. Mendeleev's law of the periodic table states that chemical and physical properties of elements vary in a predictable fashion based on their atomic weights. The current periodic table of elements is based on the fact that the properties of elements change with their atomic number. The elements of Mendeleev's table were organized in rows called periods and columns called groups. Elements belonging to the same group showed related properties. There are several regions in the periodic table called periodic table blocks, as they are named according to the sub-shell of the last electron of the atom.

Properties
The Metalloids as a group share properties of metals as well as nonmetals. Several of the metalloids are considered to be semiconductors.

Metalloids have many if not all the characteristics that metals do. Just like metals, metalloids are generally shiny, and they have low electronegativities and low ionization energies. Like metals they are ductile, which means they can be shaped into wire. Also metalloids are malleable. Metalloids can have fairly high densities, however, not as high as regular metals. Metalloids share these properties with metals due to the arrangement of their valence electrons. Metalloids also share some characteristics of nonmetals. Most nonmetals are dull in appearance and are not very shiny. They are very poor conductors of electricity as well as poor conductors of heat. Nonmetals have higher electronegativities and are looking to gain or share electrons. Nonmetals have between 4 and 8 valence electrons. All metalloids are solids at standard pressure and temperature(STP). They vary in density and at the temperature that they boil or melt at. A few of the metalloid elements are considered semiconductors, meaning they can carry an electrical charge.

Uses
Now more than ever, semiconductors are being used in our everyday lives. Metalloids are a key component in the many electronics that we use everyday. One use for semiconductors is in the field of light emitting products. The major use of these semiconductors is found in all circuit boards and in all electronic devices. The most common used of these is Silicon. Silicon has its primary uses in diodes and transistors. The market for silicon is constantly growing and as one can imagine, has become very large. Metalloids are also used in memories for computers and appear in several other parts of the computer. Photosensors, strain gauges, and radiation detectors also use silicon. Almost every electrical item that can be found today utilizes semiconductors.

Here are several uses for specific metalloids: Boron is used to control the travail of borosilicate glass. These glasses accept a wanted resistance to thermal excite which causes marked glasses to breach. Silicon is used in electronic devices. Specifically in computers, transistors, solar cells, and LCD screens to control the progress of electricity. Germanium can be used to direct solar panels to control the motion of electricity. Arsenic can be used to prop up the mingle of nickels and can be found in car batteries. Antimony drugs are located in varied medications used to fight off diseases. Tellurium's major use is alloying. It increases the resilience and durability of metals. Polonium's property of being indubitable is used in the brushes used to unsoiled camera lenses and photographic films.

Metalloids in History
Throughout history, silicon has been the most important metalloid. For hundreds of years Silicon was used as a compound. As the nineteenth century came about silicon was also being used in its isolated form. Antimony and arsenic were also used in the past. These elements were given special attention by those who studied and practiced alchemy. These alchemists also believed that Tellurium was an impure state or immature state of gold.