Assertion: Graphite is an allotrope of carbon.
Reason: Graphite has a layered structure with strong covalent bonding within the layers and weak van der Waals forces between the layers.
Both A and R are true and R is the correct explanation of A
Both A and R are true but R is not the correct explanation of A.
A is true but R is false.
A is false but R is true.
The assertion is true. Allotropes are different structural forms of an element in the same physical state. Carbon has several allotropes, including diamond, graphite, fullerenes, carbon nanotubes, and amorphous carbon. Graphite is a soft, black, lustrous mineral composed of carbon.
The reason is also true. Graphite has a layered structure in which each carbon atom is bonded to three other carbon atoms in a hexagonal arrangement, forming a planar sheet. Within each layer, the carbon-carbon bonds are strong covalent bonds. However, the bonding between the layers is weak van der Waals forces, allowing the layers to slide past each other easily. This results in graphite's unique properties, such as its softness, lubricating ability, and electrical conductivity along the layers.
Therefore, both the assertion and the reason are correct, and the reason explains why graphite is an allotrope of carbon.