Slide 1 of 58  The enthalpy change that occurs in the formation of one mole of a substance in the standard state from the reference forms of the elements.

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Presentation transcript:

Slide 1 of 58  The enthalpy change that occurs in the formation of one mole of a substance in the standard state from the reference forms of the elements in their standard states.  The standard enthalpy of formation of a pure element in its reference state is 0. Hf°Hf° 7-8 Standard Enthalpies of Formation

Slide 2 of 58 Standard States

Slide 3 of 58 Standard Enthalpy of Formation

Slide 4 of 58 Standard Enthalpies of Formation

Slide 5 of 58 Standard Enthalpies of Reaction  H overall = -2  H f ° NaHCO 3 +  H f ° Na 2 CO 3 +  H f ° CO 2 +  H f ° H 2 O

Slide 6 of 58 Enthalpy of Reaction  H rxn =   H f ° products -   H f ° reactants

Slide 7 of 58 Table 7.3 Enthalpies of Formation of Ions in Aqueous Solutions

Slide 8 of 58  Worked Examples Follow:

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Slide 13 of 58  Try these end of chapter problems starting on page 266:  # 1, 5, 9, 11, 19, 25, 29, 35, 39, 45, 51, 55, 57, 59, 65, 69, 71, 75, 113, 114, 116, 117