It doesnt matter how you get there h heat of

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(It doesn’t matter how you get there) H Heat of formation = change in enthalpy that accompanies the formation of 1 mole of the compound from its elements
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4 Thermodynamics Standard conditions = conc. of 1 M, 25 °C, 1 atm (It doesn’t matter how you get there) Bond Dissociation Energy The energy absorbed or released in any reaction, symbolized by Δ H°, is called the enthalpy change or heat of reaction. Bond dissociation energy is the Δ H° for a specific kind of reaction—the homolysis of a covalent bond to form two radicals in the gas phase .
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5 Bond Dissociation Energy Because bond breaking requires energy, bond dissociation energies are always positive numbers, and homolysis is always endothermic. Conversely, bond formation always releases energy, and thus is always exothermic. For example, the H—H bond requires +104 kcal/mol to cleave and releases –104 kcal/mol when formed. Bond Dissociation Energies stronger bond, higher bond dissociation energy Can use this to predict if rxn is endothermic or exothermic
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6 Thermodynamics Standard conditions = conc. of 1 M, 25 °C, 1 atm Don’t forget entropy! (It doesn’t matter how you get there) Thermodynamics Enthalpy and Entropy Δ G° depends on both Δ H° and the entropy change, Δ S°. Entropy change, Δ S°, is a measure of the change in the randomness of a system.
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