Examples of Metalloids

Examples of metalloids

All the metalloids that exist are:

• Boron
• Silicon
• Germanium
• Arsenic
• Antimony
• Tellurium
• Astat

Boron

Boron is the metalloid that heads group IIIA of the periodic table. It has a very high melting point and properties in which the non-metallic character predominates. It is not free in its natural state, but it is the fundamental element of borax Na ₂ [B ₄ O ₅ (OH) ₄ ] * 8H ₂ O. Borax is used as a water softener and in cleaning agents.

Boric acid H ₃ BO ₃ is a mild antiseptic used in eye washes. Boron compounds are used extensively in Pyrex glassware, fiberglass, abrasives, cutting tools, porcelain enamels, and as a flame retardant. From a chemical point of view, boron behaves more like the silicon metalloid than metallic aluminum.

Its properties are as follows:

• Atomic number: 5
• Atomic weight: 10.81 g / mol
• Electronegativity: 2.04
• Density 2460 Kg / m ³
• Melting point 2076 ° C
• Boiling point 3927 ° C

Silicon

Silicon is a metalloid with predominantly non-metallic properties. It is the second most abundant element in the earth’s crust, covering 26% of it, but it is not found as a free element. Quartz sand, which is silicon dioxide (SiO ₂ ) , is used in the production of glass and cement.

This metalloid has had a wide participation in modern technology, as highly pure silicon is used in the manufacture of semiconductors and computer chips. The silicon carbide (SiC) , with trade name Carborundum is used in the creation of cutting and grinding tools.

Its properties are as follows:

• Atomic number: 14
• Atomic weight: 28.085 g / mol
• Electronegativity: 1.9
• Density 2330 Kg / m ³
• Melting point 1414 ° C
• Boiling point 2900 ° C

Germanium

Germanium is a brittle, shiny grayish-white metalloid. It is resistant to acids and bases. It is capable of forming numerous organometallic compounds, and it is a relevant semiconductor material, used to manufacture transistors and photodetectors.

Unlike some semiconductors, germanium has a short forbidden band , known as the band gap . Therefore, it responds effectively to infrared radiation and can be used in low intensity amplifiers. Its applications are limited by its high cost, and in several cases its substitution by cheaper materials is being investigated.

Germanium is used to produce fiber optics, electronic components for radars and electric guitar amplifiers, silicon-germanium alloys (SiGe) for high-speed integrated circuits, spectroscopes, night vision systems, lenses with high refractive index, and in alloys with aluminum, magnesium and tin, to harden each one of them.

Its properties are as follows:

• Atomic number: 32
• Atomic weight: 72.63 g / mol
• Electronegativity: 2.01
• Density 5323 Kg / m ³
• Melting point 938 ° C
• Boiling point 2820 ° C

Arsenic is a metalloid with properties in which the non-metallic character predominates. Both elemental arsenic and its compounds are toxic, in part because this element almost exactly mimics the chemical behavior of phosphorus without being able to function like it in living tissues, leaving lethal results.

Long exposure to high levels of inorganic arsenic can take many forms, such as drinking contaminated water or eating food prepared with it. Also food crops irrigated with this water can cause chronic poisoning. The most characteristic consequences are the appearance of skin lesions and skin cancer.

This element is used for the manufacture of agricultural insecticides and fungicides. In addition, it is an ingredient in semiconductor components and participates in the creation of lasers.

Its properties are as follows:

• Atomic number: 33
• Atomic weight: 74.92 g / mol
• Electronegativity: 2.0
• Density 5727 Kg / m ³
• Melting point 614 ° C
• Boiling point 817 ° C

Antimony

Antimony is a metalloid with predominantly metallic properties. The element is brittle and flaky, with a metallic luster. It is used to increase the hardness of lead in automobile batteries and in cable jackets. Certain antimony compounds are used in paint pigments, ceramic glazes, and fireproofing agents.

Its properties are as follows:

• Atomic number: 51
• Atomic weight: 121.76 g / mol
• Electronegativity: 2.05
• Density 6697 Kg / m ³
• Melting point 631 ° C
• Boiling point 1587 ° C

Tellurium

Tellurium is a metalloid that has a metallic appearance, but mostly non-metallic properties. It is used in semiconductors and to harden the lead plates of automobile batteries and cast iron. It is present in nature in various chemical compounds, but its abundance is not so great.

It was originally used as an additive to steel to increase its ductility, as a brightener in electroplating, as an additive in catalysts for the disintegration of petroleum and as a colorant for glasses.

Its properties are as follows:

• Atomic number: 52
• Atomic weight: 127.60 g / mol
• Electronegativity: 2.1
• Density 6240 Kg / m ³
• Melting point 450 ° C
• Boiling point 988 ° C

Astat

The astat is the last element in group VIIA, made up of halogens. It is listed as a metalloid, and it is a radioactive element. It is, after francium, the rarest element in nature; there are 25 grams or less of it at the same time, before disintegrating. It is for this very reason that some of its properties cannot be carefully measured.

Its measurable properties are as follows:

• Atomic number: 85
• Atomic weight: 210 g / mol
• Electronegativity: 2.0
• Melting point 302 ° C