alleryWhy is ∆H of C + ½O2 → CO not measured directly?
ACO cannot exist at 298 K
BSome CO2 always forms as well
CGraphite will not burn at all
DThe reaction is far too slow
Answer & Solution
Correct answer: B. Some CO2 always forms as well
Burning carbon always yields some CO2 alongside CO, so Hess's law is used instead.
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