Question

Which of the following elements is a metalloid?
A.Lithium
B.Beryllium
C.Boron
D.Carbon

Answer 1

Metalloids are a very small group of elements found in the periodic table. They have properties that are intermediate between metals and nonmetals. To solve this question, we need to know the physical and chemical properties of these compounds.

Complete step by step answer:
Basically, metalloids are defined as the chemical elements whose physical and chemical properties fall in between the metal and the non-metal categories. Some of the most widely recognized metalloids are boron, germanium, silicon, antimony, arsenic and tellurium. Moreover, metalloids have metallic appearances but they are usually brittle and only mediocre electricity conductors. They also have the ability to form metallic alloys. In general, these compounds are extremely fragile and therefore do not have many structural applications.
Now, let’s discuss some of the properties of metalloids.
1.They typically look like metals but they often behave like non-metals.
2.Physically they are brittle, shiny substances that are usually solid at ambient temperatures.
3.They are known to have electronic band structures that are similar to semiconductors.
4.They are known to form amphoteric or weakly acidic oxides.
5.They have the ability to form metallic alloys.
So, from the given options, Boron is a metalloid.

Hence, option C is correct.

Note: Boron has the ability to form intermetallic compounds. In fact, Ferro boron which contains $15\%$ boron is widely used in order to inject boron into steel. Moreover, nickel boron alloys are used as ingredients in the engineering industry for welding alloys. Germanium is also known to form several alloys and silicon alloys of aluminum and iron are also used in automobiles and construction.