According to Hess’s law, the enthalpy change being a state function is same for a rection irrespective of the path followed by it. Meaning:
if we have a reaction A to D. and enthalpy of this reaction Had
Another set of reactions A to B to C to D having enthalpies Hab , Hbc , Hcd
According to EHess law, it will be:
Had = Hab + Hbc +Hcd
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