Part II - Free Response Questions & Answers 1970 to 2007
Thermodynamics
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1970
Consider the first ionization of sulfurous acid:
H2SO3(aq) ( H+(aq) + HSO3-(aq)
Certain related thermodynamic data are provided below: H2SO3(aq) H+(aq) HSO3-(aq) ----------------- ---------- ------------------
Hf( kcal/mole -145.5 0 -151.9
S° cal/mole K 56 0 26
(a) Calculate the value of ΔG° at 25°C for the ionization reaction.
(b) Calculate the value of K at 25°C for the ionization reaction.
(c) Account for the signs of ΔS° and ΔH° for the ionization reaction in terms of