What is the composition of the compound called heat or structure enthalpy ?

What is the composition of the compound called heat or structure enthalpy ?
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The change in enthalpy that occurs during the production of one mole from the constituent elements of a compound in the state of proof is called the formation of heat or formation enthalpy of the compound. The enthalpy formed at a temperature of 25 ° C and a pressure of 1 atm is expressed by ∆ H ° f .
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