Two forms of carbon are graphite, the soft, black, slippery material used in "lead" pencils and as a lubricant for locks, and diamond, the brilliant, hard gemstone. Using the enthalpies of combustion for graphite (-396 kJ/mole C) and diamond (-396 kJ/mole C) calculate the change in H for conversion of graphite to diamond.

C graphite (s) -> C diamond (s)

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