where are they commonly applied?
Alloying components, biological agents, catalysts and flame retardants.
Metalloid
 They and their compounds are used as (or in) alloying components, biological agents (toxicological, nutritional, and medicinal), catalysts, flame retardants, glasses (oxide and metallic), optical storage media and optoelectronics, pyrotechnics, semiconductors, an
what is the basis of arranging the elements in the modern periodic table Atomic number, electron configuration, and recurring chemical properties. what is the purpose of the table? UNANSWERABLE why is called so? Because of the tabular display of the chemical elements. what sorts of elements can we see in it? Nonmetallic elements such as metalloids,  groups of families of elements and elements having metallic lustre. can you name a few of the first form? Boron, silicon, germanium, arsenic, antimony, and tellurium.
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Metalloid [SEP] Common applications
Metalloids are too brittle to have any structural uses in their pure forms. They and their compounds are used as (or in) alloying components, biological agents (toxicological, nutritional, and medicinal), catalysts, flame retardants, glasses (oxide and metallic), optical storage media and optoelectronics, pyrotechnics, semiconductors, and electronics.