AP Chemistryeasymcq1 pt
Reversing a reaction changes its ΔH how?
A.The sign flips
B.The magnitude doubles
C.It stays identical
D.It becomes zero
Explanation
Core Concept
If A → B releases 100 kJ, then B → A must absorb 100 kJ — enthalpy changes sign on reversal, a direct consequence of Hess's law.
Correct Answer
AThe sign flips
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