Graphite

Graphite

Graphite is an allotrope of Carbon. Graphite has layered structure. Layers are held by van der Waals forces and distance between two layers is 340 pm. Each layer is composed of planar hexagonal rings of carbon atoms. C-C bond length within the layer is 141.5 pm. Each carbon atom is hexagonal ring undergoes sp² hybridization and makes three sigma bonds with three neighboring carbon atoms. Fourth electron forms a n bond. The electrons are delocalized over the whole sheet. Electrons are mobile and, therefore, graphite conducts electricity along the sheet. Graphite cleaves easily between the layers and, therefore, it is very soft and slippery.

Uses

For its soft and slippery character, graphite is used in machines running at high temperature, where oil cannot be used as a lubricant.