AP Chemistryeasymcq1 pt
Given: C(s) + O₂(g) → CO₂(g), ΔH = −393.5 kJ. What is ΔH for CO₂(g) → C(s) + O₂(g)?
A.+393.5 kJ
B.−393.5 kJ
C.0 kJ
D.−787.0 kJ
Explanation
Core Concept
The reverse reaction absorbs exactly what the forward releases: ΔH flips sign. Decomposing CO₂ into its elements costs +393.5 kJ/mol.
Correct Answer
A+393.5 kJ
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