Assertion(A) : Graphite is slippery and used as a lubricant.
Reason (R) : Graphite has free electrons.
Answer: B
Graphite possesses a layer structure with two successive layers held by weak forces and able to slide over one another. So, graphite is slippery and this property finds its use as a lubricant. In graphite, each carbon atom is linked to three other carbon atoms while one electron in the carbon atom is delocalised. So, graphite has free electrons