Question

Diamond is the hardest allotrope of Carbon. Give reason for its hardness.

Answer 1

Diamond is the hardest mineral known (10 on the Mohs scale), but graphite is one of the softest (1–2 on Mohs scale). Diamond is the ultimate abrasive, but graphite is soft and is a very good lubricant. Diamond is an excellent electrical insulator, but graphene is an excellent conductor

Answer 2

• Diamond made up of carbon atoms.
• The outermost shell of each carbon atom has four electrons.
• In diamond, these electrons are shared with four other carbon atoms to form very strong chemical bonds resulting in an extremely rigid tetrahedral crystal.
• It is this simple, tightly-bonded arrangement that makes diamond one of the hardest substances on Earth.

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