alleryStart learning →In gas-phase reactions, ΔrH approximately equals what?
ASum of bonds formed minus bonds broken
BSum of bonds broken minus bonds formed
CSum of product bond enthalpies only
DLattice plus hydration enthalpy
Answer & Solution
Correct answer: B. Sum of bonds broken minus bonds formed
Energy is needed to break reactant bonds and is regained on forming product bonds, so ΔrH is reactant bond enthalpies minus product bond enthalpies.
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