Chemistry
State what are metalloids. Name the elements recognized as metalloids. Compare the properties of metalloids with those of metals. State the uses of three different metalloids.
Answer
Metalloids are elements that show the properties of both metals and non-metals. They have physical and chemical properties, intermediate between those of metals and non-metals.
Elements like Boron [B], Silicon [Si], Germanium [Ge], Arsenic [As], Antimony [Sb], Tellurium [Te] are recognized as metalloids.
Comparison of properties:
| Property | Metal | Metalloids |
|---|---|---|
| State | Solids at room temperature | Solids at room temperature |
| Nature | Generally, hard in nature. | Brittle in nature. |
| Conductivity | Good conductors of heat and electricity. | Semi conductors of electricity and show average transmission of heat. |
| Lustre | Show brightness | Show brightness |
| Malleability & Ductility | Malleable and Ductile | Generally malleable and Ductile |
Use of metalloids:
- Boron — is used as an insecticide and a fire retardant.
- Arsenic — is used for certain medicinal purposes.
- Silicon — Silicon gel is generally applied to burn patients and to absorb moisture.
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