Question

What is the chemical formula of graphite?

Answer 1

Hint:Graphite is an allotrope of carbon and so it is made up of carbon atoms in a geometric arrangement. The combustion of graphite produces carbon dioxide that confirms the presence of carbon in the substance.

Complete answer:
Graphite is known as an allotrope of carbon like diamond. It contains a hexagonal arrangement of carbon atoms in two dimensions. Graphite is the most stable form of carbon in nature.
Under high pressures and temperatures the geometric arrangement of the carbon atoms changes and it converts to diamond. The primary use of graphite is in making pencils and lubricants. It serves as a good conductor of heat and electricity and hence is used in electronic products such as electrodes in batteries, and solar panels.
Thus the chemical formula of graphite is $$C$$ . Graphite contains repeating units of carbon atoms. The carbon atoms are held together by two types of bonds. The covalent bonds are present between the carbon atoms to hold the hexagonal structure. The Vander Waal bonds are present between the two layers of the hexagonal packing of carbon atoms.
In graphite the carbon atoms are $$s{p}^2$$ hybrid orbitals and each atom in planes is bound to three nearest carbon atoms neighbors at an angle of $${120}^o$$. The individual layers are called graphene.
Each layer consists of a honeycomb lattice with a bond length of $$0.142nm$$ and the distance between the different planes is $$0.335nm$$. Out of the four electrons in carbon atom three are used to form bonds with three carbons in plane and the fourth electron is free to migrate in the plane which makes graphite electrically conductive. The weak Vander Waals bonds between two layers makes graphite slippery and so the layers slide past each other.

Note:
Graphite was also known as black lead or plumbago. The graphite is soft due to the layer-like structure of carbon atoms. It is electrically conducting due to the presence of free electrons.