AP Chemistryeasymcq1 pt
Which substance has a nonzero standard enthalpy of formation?
A.CO₂(g)
B.C(s, graphite)
C.H₂(g)
D.N₂(g)
Explanation
Core Concept
CO₂ is a compound, so its ΔH°_f (−393.5 kJ/mol) is nonzero. Only elements in their standard states are defined as zero.
Correct Answer
ACO₂(g)
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