Elemental carbon usually exists in one of two forms: graphite or diamond. It is generally believed thatdiamonds last forever. The table shows the standard enthalpy of formation (AH;) and the standardmolar entropy (S°) values for diamond and graphite.Substance AH; (kJ/mol) S° (J/mol · K)Cgraphite5.740Cdiamond1.8972.38 What is the standard Gibbs free energy for the transformation of diamond to graphite at 298 K?Cdiamond →CgraphiteExpress your answer to three significant figures and include the appropriate units.

The given reaction is as follows: Cdiamond → Cgraphite The standard Gibbs free energy = ? Calculation of standard enthalpy of the reaction: ∆Hr°=ΣHf°(Products)-ΣHf°(Reactants)=Hf°(Cgraphite)-Hf°(Cdiamond)=0-1.897 kJ/mol=-1.897 kJ/mol Calculation of standard entropy of the reaction: ∆Sr°=ΣS°(Products)-ΣS°(Reactants)=S°(Cgraphite)-S°(Cdiamond)=5.740 J/mol.K-2.38 J/mol.K=3.36 J/mol.K Calculation of standard Gibbs free energy of the reaction: ∆Gr°=∆Hr°-T∆Sr°=1.897×1000 J/mol-298 K×3.36 J/mol.K=1897 J/mol-1001.28 J/mol=895.72 J/mol=0.89572 kJ/mol=0.896 kJ/mol Hence, the standard Gibbs free energy for the reaction is 0.896 kJ/mol.

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What is the standard Gibbs free energy for the transformation of diamond to graphite at 298 K? Cdiamond →Cgraphite Express your answer to three significant figures and include the appropriate units.

What is the standard Gibbs free energy for the transformation of diamond to graphite at 298 K? Cdiamond →Cgraphite Express your answer to three significant figures and include the appropriate units.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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