State Hess’s law of constant heat summation.Give its two applications.

State Hess’s law of constant heat summation.Give its two applications.
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1 Answer

Answer :

Ans. Hess’s law states that enthalpy change for a reaction is same whether the reaction occurs in single step or several steps.
OR If a reaction occurs in several steps then ,its standard enthalpy of reaction is equal to the sum of standard enthalpies of the intermediate reactions into which the overall reaction may be divided at the same temperature.
Applications:
(i) It is used to calculate enrhalpy of the formation of the compound
(ii) It is used to calculate Lattice enthalpy of an ionic solid.
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