MCQ
Thermodynamically, the most stable form of carbon is
  • A
    Diamond
  • Graphite
  • C
    Fullerenes
  • D
    Coal

Answer

Correct option: B.
Graphite
b
Graphite is thermodynamically, the most stable allotrope of carbon. That is why $\Delta _fH^o$ (graphite) is taken as zero.

$\Delta _fH^o$ (diamond) $= +1.90\,kJ\,mol^{-1}$

$\Delta _fH^o$ (fullerene) $= +38.1\,kJ\,mol^{-1}$

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