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Given entropy -189.2j/mol and enthalpy -201kj/mol, predict how the Gibbs free energy changes with temperature for the reaction?

User Digisec
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Final answer:

Using the Gibbs free energy equation ΔG = ΔH - TΔS, with given values of entropy and enthalpy, the Gibbs free energy of the reaction becomes more negative with increasing temperature, suggesting the reaction becomes more spontaneous at higher temperatures.

Step-by-step explanation:

To predict how the Gibbs free energy changes with temperature for the reaction given the entropy (ΔS) of -189.2 J/mol and enthalpy (ΔH) of -201 kJ/mol, we use the Gibbs free energy equation ΔG = ΔH - TΔS. Prior to substitution into the equation, the entropy change should be converted to kJ/K · mol by dividing by 1000, and the temperature should be in Kelvins.

ΔG changes with temperature because the TΔS part of the equation is temperature-dependent. If we were to graph ΔG against temperature, we would expect to see a linear relationship where ΔG becomes more negative as TΔS becomes more positive with increasing temperature.

This process is typically carried out at elevated temperatures, so a larger TΔS value would mean that the negative ΔG becomes even more negative, thereby predicting increased spontaneity with rising temperature.

User ChrisCantrell
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