alleryStart learning →How is the reaction enthalpy ΔrH calculated from molar enthalpies?
ASum of reactants minus sum of products
BSum of products plus sum of reactants
CSum of products minus sum of reactants
DAverage of products and reactants
Answer & Solution
Correct answer: C. Sum of products minus sum of reactants
The reaction enthalpy is the total enthalpy of products minus that of reactants, so exothermic reactions give a negative value.
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