Properties of Metalloids: Informative Guide

Metalloids are highly common elements found in the periodic table between metals and non-metals. These materials are used in many applications and have unique characteristics.

If you are planning to use them in your applications and want to learn more about the properties of metalloids, the guide below can help you. So, let's read.

What are Metalloids?

Metalloids are defined as chemical elements that have chemical as well as physical properties somewhere between metal and non-metals.

There are different types of metalloids with unique characteristics. The metalloids are in the p-block of a periodic table and are present between the metals and non-metals.

What are the Typical Elements of Metalloids?

The different elements which fall under the category of metalloids are as follows:

Boron (B)

Boron is a metalloid that has an atomic number of 5, and it is used in chemical compounds widely. Boron has a crystalline form and a black color; it is a very hard metal.

It is used for hardening glass and steel. Boron-based components like fertilizers and insecticides are used for plant growth.

Arsenic (As)

Arsenic is a risky element that can interfere with humans' respiration process. It has an atomic number of 33.

It can form 3 covalent bonds with metals and is toxic for plants as well as animals. It is used to harden metal alloys and leads. It is also used as an insecticide.

Silício (Si)

Silicon is a versatile metalloid that is very common in the construction industry and also in semiconductors.

It has an atomic number of 14 and is very reactive, commonly found in soils, sand, and rocks. It is a poor electrical conductor and is used in manufacturing enamels, glass, ceramics, and semiconductors.

Antimónio (Sb)

Antimony has 51 as its atomic number and is used in paints and alloys. It has a metallic appearance in silver-white. It is brittle and hard in nature. It is a poor electrical conductor and is used in semiconductors in the form of a dopant and also for manufacturing enamel and glass.

Tellurium (Te)

Tellurium is an alloying element that has 52 as its atomic number. It is found in mined ores and has a brittle nature. It dissolves in nitric acid and remains insoluble in water. It makes the alloys resistant to corrosion.

Germanium (Ge)

Germanium is used in transistors and has an atomic number of 32. It has a metallic look and is brittle in nature. It offers poor electrical conductivity and enhances the corrosion resistance of alloys. It is also used in detectors, which are made using infrared and even semiconductors.

Physical Properties of Metalloid

The physical properties of metalloids are highlighted in the section below.

Appears to Have Metallic Luster

Metalloids have a look that is similar to metals– they have a reflective and metallic surface.

Boiling and Melting Points

Metalloids are solid when at room temperature.

Densidade

The density of metalloids varies from one another but is less than that of metals and more than non-metals.

Condutividade eléctrica

Metalloids can work like insulators as well as conductors. They can be modified as per requirements.

For instance, when used for semiconductors, they pass through the process of doping. It is the process in which impurities are added to the metalloids to alter their properties. However, they are still not as conductive as metals in electricity.

Allotropes

Most of the metalloids can offer different allotropic forms as they have different physical properties. The three common allotropes of arsenic are gray, yellow, and black.

Condutividade térmica

The thermal conductivity of the metalloids varies from element to element. They generally have lower thermal conductivity than metals and higher thermal conductivity than nonmetals.

Brittleness

Metalloids are prone to cracking and deforming due to their brittle nature.

Dureza

Metalloids have variable hardness, with arsenic having a hardness of 3.5, whereas boron has a hardness of 9.3.

Chemical Properties of Metalloids

The chemical properties of metalloids compose the following:

Reactivity with Nonmetals

Metalloids are reactive and can easily gain and lose electrons so that they can form ions which can be negatively or positively charged. They also combine with non-metals to form compounds.

Oxidation States

The oxidation states of metalloids vary and are featured in the table below:

Moderate Ionization Energy

Metalloids have moderate ionization energy, which ranges around 200 kcal/mol.

Intermediate Electronegativities

Covalent Bonds

Metalloids are known to create covalent bonds. However, they do not make monoatomic ions similar to metals.

Alloy Formation

Metalloids are very commonly mixed with other elements to form alloys.

Reactivity with Acids

Metalloids have less reactivity with acids. For example, germanium and silicon are insoluble and do not react with acids. Arsenic and antimony react with strong acids.

Known as Amphoteric

Metalloids have properties of both metals as well as non-metals, which makes them known as amphoteric.

Applications of Metalloids

Metalloids have various applications, and some of these are discussed below:

Semiconductors: In semiconductors, germanium and silicon are used, and they can be used in computer chips, integrated circuits, and even solar cells. They have semiconducting properties, which is why they play a crucial role in electronics.

Ceramics and Glass: Arsenic, boron, and silicon are commonly used in ceramics and glass as they can work like a refractory agent. Borosilicate glass is also made using them as it can resist chemicals as well as thermal shock.

Alloys: Many alloys also have metalloids to enhance their properties. For instance, silicon is added to aluminum so that it can have more castability and strength. In steel, boron is added to enhance its hardness.

Photovoltaics: Solar cells and some metalloids, like germanium and silicon, are used to help convert sunlight into electricity.

Flame Retardants: Boron compounds, antimony trioxide, and aluminum trihydrate are used to work as flame retardants in many coatings, plastics, and building materials. They help with fire safety.

Distinguishing and Most Useful Properties of Metalloids

The distinguishing properties of each metalloid and its applications are discussed below:

Boron: It is hard and resistant to heat; it is used in combination with silicon to create a glass that can resist thermal shock.

Germanium: Germanium is brittle and hard and very rarely used in semiconductors.

Silicon: Silicon is a shiny and gray metalloid that is used in semiconductors.

Tellurium: It has a brittle nature and enhances machinability when combined with steel.

Arsenic: It is a poisonous metalloid and is used in insecticides.

Antimony: It is brittle and hard, is alloyed with lead, and is even used for manufacturing paints.

Differences Between Metalloids, Metals, and Nonmetals

Final Thoughts

When it comes to choosing between metals, non-metals, and metalloids, understanding their properties is crucial. The guide above must have made you understand everything about metalloids and their applications.

If you are planning to have some components manufactured using any material, we at DEK can help you.

FAQs

What composed metalloids?

Metalloids are neither metals nor non-metals but are in the middle of both having combined properties.

How can metalloids be identified?

Metalloids can be identified by looking at their properties. They have a brittle nature and lustrous appearance and stay solid at room temperature.

Can mercury be classified as a metalloid?

No, mercury cannot be classified as a metalloid.

What elements belong to the metalloid group, and how are they used?

The elements in the metalloid group consist of arsenic, boron, antimony, silicon, tellurium, and germanium. They are used in various applications, such as fertilizers, insecticides, and semiconductors.