P3D.4 The solubility of an ionic solid such as NaCl can be explored by calculating the standard Gibbs energy change for the process NaCI(s) → Na*(aq) + CI (aq). Consider this process in two steps: (1) NaCI(s) → Na*(g) + CI (g) and then (2) Na*(g) + CI (g) –→ Na*(aq) + CI(aq). Estimate A,G° for the first step given that A,H® = 787kJ mol and the following values of the absolute entropy: S(Na*(g)) = 148JK"mol", S(CI (g) = 154JK'mol", S(NaCI(s)) = 72.1 JK'mol* (all data at 298 K). The value of 4,G° for the second step can be found by using the Born equation to estimate the standard Gibbs energies of solvation. For these estimates, use r(Na*) = 170 pm and r(CI) = 211 pm. Hence find A,G° for the overall process and comment on the value you find.

P3D.4 The solubility of an ionic solid such as NaCl can be explored by calculating the standard Gibbs energy change for the process NaCI(s) → Na(aq) + CI (aq). Consider this process in two steps: (1) NaCI(s) → Na(g) + CI (g) and then (2) Na(g) + CI (g) –→ Na(aq) + CI(aq). Estimate A,G° for the first step given that A,H® = 787kJ mol and the following values of the absolute entropy: S(Na(g)) = 148JK"mol", S(CI (g) = 154JK'mol", S(NaCI(s)) = 72.1 JK'mol (all data at 298 K). The value of 4,G° for the second step can be found by using the Born equation to estimate the standard Gibbs energies of solvation. For these estimates, use r(Na*) = 170 pm and r(CI) = 211 pm. Hence find A,G° for the overall process and comment on the value you find.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter16: Thermodynamics: Directionality Of Chemical Reactions

Section: Chapter Questions

Problem 89QRT: Determine the standard Gibbs free energy change, rG, for the reactions of liquid methanol, of CO(g),...

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