Using ΔG°f tables in Appendix 1, calculate the solubility product constant, Ksp, for PbCl2 at 25°C.

Question

Using Δ[latex]G°_{f}[/latex] tables in Appendix 1, calculate the solubility product constant, [latex]K_{sp}[/latex], for [latex]PbCl_{2}[/latex] at 25°C.

ANALYSIS
equation for dissolving [latex]PbCl_{2}[/latex]([latex]PbCl_{2}[/latex](s) → [latex]Pb^{2+}(aq) + 2Cl^{-}(aq)[/latex]) T(25°C)	Information given:
Δ[latex]G°_{f}[/latex] values (Appendix 1) R value	Information implied:
[latex]K_{sp}[/latex]	Asked for:

STRATEGY

1. Obtain Δ[latex]G°_{f}[/latex] values from Appendix 1 and substitute into Equation 16.3.

[latex]ΔG°_{reaction}[/latex] = Σ[latex]ΔG°_{f_{ products}}[/latex] - Σ[latex]ΔG°_{f_{ reactants}}[/latex] (16.3)
2. Substitute into Equation 16.5 to find [latex]K_{sp}[/latex], which is K.

ΔG° = -RT ln K (16.5)

ΔG° = -RT ln [latex]K_{sp}[/latex]

Accepted Answer

ΔG° = Δ[latex]G°_{f} Pb^{2+}(aq) + 2ΔG°_{f} Cl^{-}(aq) - ΔG°_{f} PbCl_{2}(s)[/latex]

= -24.4 kJ + 2(-131.2 kJ) + 314.1 kJ = +27.3 kJ

ΔG° = -RT ln [latex]K_{sp}[/latex]; 27.3 kJ = -(0.00831 kJ/K)(298 K) ln [latex]K_{sp}[/latex]

ln [latex]K_{sp}[/latex] = -11.0 → [latex]K_{sp}[/latex] = [latex]e^{-11.0} = 1.7 × 10^{-5}[/latex]

ΔG°

[latex]K_{sp}[/latex]

END POINT

This is the value listed in Chapter 15 for [latex]K_{sp}[/latex] of [latex]PbCl_{2}[/latex].

Question 16.8: Using ΔG°f tables in Appendix 1, calculate the solubility pr...

Related Answered Questions

Verified Answer:

Using ΔG°f values from Appendix 1, calculate the standard free energy change at 25°C for the reaction referred to in Example 16.3. ...

Verified Answer:

Calcium sulfate, CaSO4, is used as a drying agent and sold under the trade name Drierite. For the reaction CaSO4(s) → Ca2+(aq) + SO42-(aq), calculate ⓐ ΔH° ⓑ ΔS° ⓒ ΔG° at 25°C ...

Verified Answer:

At what temperature does DG8 become zero for the reaction considered in Example 16.5? Fe2O3(s) + 3H2(g) → 2Fe(s) + 3H2O(g) ...

Verified Answer:

Iron, a large component of steel, is obtained by reducing iron(III) oxide (present in hematite ore) with hydrogen in a blast furnace. Steam is a byproduct of the reaction. Calculate ΔG° at 230°C for the reduction of one mole of Fe2O3. ...

Verified Answer:

Calculate ΔS° for ⓐ dissolving one mole of calcium hydroxide in water. ⓑ the combustion of one gram of methane to form carbon dioxide and liquid water. ...

Verified Answer:

Verified Answer:

CONCEPTUAL Predict whether ΔS is positive or negative for each of the following processes: (a) taking dry ice from a freezer where its temperature is -80°C and allowing it to warm to room temperature. (b) dissolving bromine in hexane. (c) condensing gaseous bromine to liquid bromine. ...

Verified Answer: