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Which one of the following statements is NOT correct?

Options

  1. ADiamond is hard due to extended covalent bonding in it
  2. BFullerene is composed of five and six membered rings
  3. CDiamond is a good conductor of electricity
  4. DGraphite is used as a lubricant

Correct answer

C. Diamond is a good conductor of electricity

Step-by-step solution

In diamond, each carbon atom is sp^3 hybridized and covalently bonded to four other carbon atoms, forming a rigid three-dimensional network. Since all four valence electrons of each carbon atom are localized in these strong covalent bonds, there are no free electrons available to conduct electricity. Thus, diamond is an insulator, not a good conductor of electricity. The other statements are correct: Diamond is extremely hard due to its extended three-dimensional covalent bonding. Fullerenes (like C₆₀ ) are compose

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