Arsenic has long played a role in murder mysteries, being used to commit the foul deed see Figure 3. This use of the material is not very smart since arsenic can be easily detected on autopsy. We find arsenic in pesticides, herbicides, and insecticides, but the use of arsenic for these applications is decreasing due to the toxicity of the metal.
Its effectiveness as an insecticide has led arsenic to be used as a wood preservative. Antimony is a brittle, bluish-white metallic material that is a poor conductor of electricity see Figure 4. Used with lead, antimony increases the hardness and strength of the mixture. This material plays an important role in the fabrication of electronic and semiconductor devices. About half of the antimony used industrially is employed in the production of batteries, bullets, and alloys.
Skip to main content. The Periodic Table. Search for:. Carbon cannot conduct electricity. Why not? What is this intricate orb? It is the greatly magnified skeleton of single-celled ocean organisms call radiolarian. The skeleton is made of an element that is extremely common on Earth. It is also one of the most common elements in the entire universe.
What is this important element? Its name is silicon, and it belongs to a class of elements called metalloids. Metalloids are the smallest class of elements. The other two classes of elements are metals and nonmetals. There are just six metalloids. In addition to silicon, they include boron, germanium, arsenic, antimony, and tellurium. Metalloids fall between metals and nonmetals in the periodic table. They also fall between metals and nonmetals in terms of their properties.
Q: How does the position of an element in the periodic table influence its properties? A: Elements are arranged in the periodic table by their atomic number , which is the number of protons in their atoms.
Atoms are neutral in electric charge, so they always have the same number of electrons as protons. It is the number of electrons in the outer energy level of atoms that determines most of the properties of elements. How metalloids behave in chemical interactions with other elements depends mainly on the number of electrons in the outer energy level of their atoms. Metalloids have from three to six electrons in their outer energy level.
Boron, pictured in the Figure below , is the only metalloid with just three electrons in its outer energy level. It tends to act like metals by giving up its electrons in chemical reactions. Metalloids with more than four electrons in their outer energy level arsenic, antimony, and tellurium tend to act like nonmetals by gaining electrons in chemical reactions. Those with exactly four electrons in their outer energy level silicon and germanium may act like either metals or nonmetals, depending on the other elements in the reaction.
Most metalloids have some physical properties of metals and some physical properties of nonmetals. For example, metals are good conductors of both heat and electricity, whereas nonmetals generally cannot conduct heat or electricity. And metalloids? They fall between metals and nonmetals in their ability to conduct heat, and if they can conduct electricity, they usually can do so only at higher temperatures.
Metalloids that can conduct electricity at higher temperatures are called semiconductors. Silicon is an example of a semiconductor. It is used to make the tiny electric circuits in computer chips. You can see a sample of silicon and a silicon chip in the Figure below. Metalloids tend to be shiny like metals but brittle like nonmetals.
Because they are brittle, they may chip like glass or crumble to a powder if struck. Other physical properties of metalloids are more variable, including their boiling and melting points, although all metalloids exist as solids at room temperature.
You can learn about the properties of specific metalloids by watching the video at this URL:. They fall between metals and nonmetals in the periodic table. Metalloids may act either like metals or nonmetals in chemical reactions. They fall between metals and nonmetals in their ability to conduct heat and electricity. Most of the metals are solids at room temperature, with a characteristic silvery shine except for mercury, which is a liquid.
Nonmetals are usually poor conductors of heat and electricity, and are not malleable or ductile; many of the elemental nonmetals are gases at room temperature, while others are liquids and others are solids. The metalloids are intermediate in their properties. In their physical properties, they are more like the nonmetals, but under certain circumstances, several of them can be made to conduct electricity. These semiconductors are extremely important in computers and other electronic devices.
On many periodic tables, a jagged black line see figure below along the right side of the table separates the metals from the nonmetals. The metals are to the left of the line except for hydrogen, which is a nonmetal , the nonmetals are to the right of the line, and the elements immediately adjacent to the line are the metalloids. When elements combine to form compounds, there are two major types of bonding that can result.
Ionic bonds form when there is a transfer of electrons from one species to another, producing charged ions which attract each other very strongly by electrostatic interactions, and covalent bonds , which result when atoms share electrons to produce neutral molecules. Skip to content Home Engineering What is special about metalloids? Ben Davis February 18, What is special about metalloids? Why are semi metals special? Why are metalloids important in modern technology?
What is the most useful property of the metalloids? What are 3 characteristics of metalloids? What is the most common metalloid? Are most metalloids radioactive? How can I remember metalloids? What are metalloids class 10th?
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