Calculate Enthalpy of Ionization of Weak Acid: ΔH3

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SUMMARY

The enthalpy of ionization for the weak acid, ΔH3, can be calculated using Hess's law, based on the provided reactions. The values obtained for ΔH1 and ΔH2 are -52.33 kJ/mol and -5.21 kJ/mol, respectively. To find ΔH3, one must manipulate the reactions to eliminate the hydroxide ion (OH-) and water (H2O) from the equations. This involves starting with the second reaction and applying the first reaction appropriately to derive the desired enthalpy change.

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Homework Statement



Find the enthalpy of ionization of the weak acid, ΔH3

H3O+ + OH- <-> 2H2O....ΔH1
HA + OH- + H2O <-> A- + 2H2O...ΔH2
HA + H2O <-> H3O+ A-...ΔH3

The Attempt at a Solution



I won't show it here but I've found ΔH1 to be -52.33 kJ/mol and ΔH2 to be -5.21 kJ/mol. I don't know how to get the third enthalpy though, I know you'd use Hess' law but I don't really understand what to do here.
 
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Obviusly you have to start with the second reaction, as it has HA and A- in correct places. Then use the first reaction to get rid of OH- on the LHS and H2O on the RHS.
 

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