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# Chemical Reactions - Temperature and Gibbs Free Energy

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1- If ΔH = -60.0kJ and ΔS = -0.200kJ/K , the reaction is spontaneous below a certain temperature. Calculate that temperature. Express your answer numerically in kelvins.

2-The chemical reaction that causes aluminum to corrode in air is given by
4Al+3O 2 →2Al 2 O 3 in which ΔH rxn ∘ = −3352 kJ and ΔS rxn ∘ = −625.1 J/K)

Part A: What is the standard Gibbs free energy for this reaction? Assume the commonly used standard reference temperature of 298 K. Express your answer as an integer and include the appropriate units.

Part B : What is the Gibbs free energy for this reaction at 5975K ? Assume that ΔH and ΔS do not change with temperature.Express your answer to two decimal places and include the appropriate units.

Part C: At what temperature, T , do the forward and reverse corrosion reactions occur in equilibrium? Express your answer as an integer and include the appropriate units.

##### Solution Summary

This solution contains detailed step-wise calculation of some numerical problems related to thermodynamics.

Solution provided by:
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