Question

Which of the foils is a semiconductor-
1. Aluminium
2.  Tungsten
3. Silicon
4. Porcelain

Answer 1

Correct Answer - Option 3 : Silicon

Silicon is the correct option.

Concept:

• Metals: The metals usually have either 1,2 and 3 electrons in the outermost shell.
  • The properties of metals include high density, electrical and heat conductivity, tensile strength, etc.
  • Examples of the metal include sodium, Iron, Calcium, etc.
• Non Metals: The non-metals usually have either, 5, 7 or 8 electrons in the outermost shell. 
  • The properties include lower density, poor conductors of electricity, and heat conductivity.
  • Examples of non-metals include Sulphur, Oxygen, Nitrogen, etc.
• Metalloids or semiconductors: The elements having physical and chemical properties with some level of similarities between both metals and non - metals are called metalloids.
  • When comes to electrical conductivity, they are neither conductors nor insulators.
  • Their conductivity lies between parameters set for both metal and non - metals. So, they are called semiconductors.
  • Examples are Silicon, Germanium.
  • They are used to make electronic components.