Question

Some allotropes of selenium display characteristics of a metalloid, even though selenium is usually considered a non-metal.
A.True
B.False

Answer 1

Hint: We must know about the word metalloids. Metalloids are elements which have properties in between metal and non-metal. We know that a nonmetal is a chemical element that lacks the metallic properties.

Complete step by step answer:
Let’s start with what are metalloids? Well, metalloids are a group of elements which are neither metal or non-metal. These elements form a zigzag line in a periodic table which distinguishes between the metal and non-metals. The elements having properties which are in between the metals and non-metals are metalloids. Metalloids act as good semiconductors along with electronegativity located between those of metals and non-metals.
We know that the nonmetal elements are located at the upper right-hand corner of the periodic table.
A chemical element which does not show metallic properties and has the ability of forming anions, acid oxides, acids, and stable hydrogen compounds are non-metals.
We also know that non-metals are brittle and we cannot roll them into sheets. They are poor conductors of heat and electricity. They also have a tendency to gain or share electrons with other species.
Selenium can be found to be multiple allotropes that are necessarily diverse molecular forms of an element with difference in physical properties.
For example, one allotrope of selenium can be seen as an amphorous red powder.
Selenium also takes a crystalline hexagonal structure, giving rise to a metallic gray allotrope that is said to be stable. The most thermodynamically stable allotrope of selenium is trigonal selenium and is gray in colour. Most selenium is obtained from the electrolytic refining process of copper. This is generally found as red allotrope.
Certain allotropes of selenium show features of metalloids, although selenium is considered as a non-metal. In environmental chemistry, we consider selenium as a metalloid because of its similarities with antimony and arsenic in aquatic chemistry.

The given statement is (A) True.

Note:
We must understand that the metalloids are half-metals. The property of metalloids is strange. Because it looks like metal but it has chemical behaviour as non-metal. We can use metalloids in electrical components because of its semiconductor property. For example, we can use silicon to make computer electrical components. Also we can use metalloids for fireworks, cleaning, cosmetics etc.