The diagram shows reactants and products related to elements in their standard states via formation enthalpies.
Which formula gives ΔH°rxn from standard enthalpies of formation?
- A
ΣΔHf°(reactants) − ΣΔHf°(products)
- B
ΔHf°(any product alone)
- C
ΣΔHf°(products) + ΣΔHf°(reactants)
- Dcheck_circle
ΣΔHf°(products) − ΣΔHf°(reactants)
Explanation
By Hess's law applied to the formation cycle, ΔH°rxn = ΣnΔHf°(products) − ΣmΔHf°(reactants).