Question

5. What are metalloids? How do their properties justify their name?

Answer 1

Part-1: Definition of metalloids:

The metalloids are a group of six elements listed in the periodic table between metals and non-metals. They are boron, silicon, germanium, arsenic, antimony, and tellurium. Silicon is the most abundant metalloid in the Earth's crust. Sand is nothing but silicon dioxide.

Part-2: Properties:

Some properties of metalloids are similar to those of metals, while others are similar to those of non-metals. Hence, they justify the name metalloids.

• Physical state: All metalloids are solids, like metals.
• Hardness and strength: Metalloids are brittle, that is, easily breakable.
• Luster: Metalloids have some luster.
• Conduction of heat and electricity: Silicon, germanium, and tellurium conduct electricity under the right conditions. They are semiconductors. Metalloids conduct less heat than metals.
• Malleability, ductility, and sonority: Metalloids are not malleable, ductile, or sonorous.
• Melting and boiling points: Metalloids have melting points, boiling points, and densities intermediate between those of metals and non-metals.