Carbon, Diamond, and Graphite are collectively called what?

Carbon, Diamond, and Graphite are all forms of the element carbon, but they differ in structure and properties. These different forms are called allotropes. Allotropy is the phenomenon in which an element exists in two or more forms in the same physical state but with different molecular arrangements and physical properties.

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  Diamond: In diamond, each carbon atom is tetrahedrally bonded to four other carbon atoms, forming a rigid three-dimensional lattice. This structure makes diamond extremely hard, transparent, and an excellent insulator.

  
  


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  Graphite: In graphite, carbon atoms are arranged in layers of hexagonal sheets. Each carbon is bonded to three others, leaving delocalized electrons that allow graphite to conduct electricity. Graphite is soft, slippery, and used in pencils and lubricants.

  
  


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  Carbon (amorphous): Carbon can also exist in non-crystalline forms like charcoal or soot, which have random structures.

  
  

These differences arise from the bonding and arrangement of carbon atoms. Diamond and graphite have the same chemical composition (pure carbon) but different physical and chemical properties, which is the hallmark of allotropy.

Other options are incorrect:

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  Isomers refer to compounds with the same chemical formula but different arrangements of atoms in molecules.

  
  


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  Isomorphs are compounds that have the same crystal structure.

  
  


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  Isotopes are atoms of the same element with different numbers of neutrons.

  
  

Understanding allotropes is essential in Chemistry, as it demonstrates how atomic arrangement affects physical properties, industrial applications, and uses in materials science. For example, diamonds are used in cutting tools, while graphite is used in electrodes and lubricants.

Allotropy highlights the versatility of elements like carbon and is a key concept in material chemistry and everyday science.