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If CaCO3, CaO and 1.0 M CO2 are placed in a flask, will the reaction release heat energy or require heat energy at 25°C. The (delta)G°rxn = 179.2 kJ and the (delta)H°rxn is 131.4 kJ. Explain your reasoning!
CaCO3(s) <----> CaO(s) + CO2(g)
CaO(s) S° = 38.1, CO2(g) S° = 213.8, CaCO3(s) S° = 91.7
ReplyDeletedelta S° = 38.1 + 213.8 - (91.7) = 160.2 J x I kJ/1000 J = 0.1602 kJ
179.2 = 131.4 - T(0.1602)
T = - 298.4 K or -25.4 °C
It will require heat energy at 25 °C meaning it's an endothermic reaction (delta H is positive). At high temperatures this reaction will be spontaneous.
Not the correct processing. No need to calculate the entropy. Think about the fact the we have an "initial" concentration of CO2.
DeleteThanks for your responses!
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