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title: "A student prepares a saturated solution of lead(II) iodide by adding solid \\(\\text{PbI}_2\\) to distilled water at \\(25^\\circ\\text{C}\\) until excess solid remains at the bottom of the beaker:  \\[ \\text{PbI}_2(s) \\rightleftharpoons \\text{Pb}^{2+}(aq) + 2\\,\\text{I}^-(aq) \\]  The value of \\(K_{sp}\\) for \\(\\text{PbI}_2\\) at \\(25^\\circ\\text{C}\\) is \\(3.2 \\times 10^{-8}\\). Assuming no other equilibria occur, what is the concentration of \\(\\text{I}^-(aq)\\) in the saturated solution at \\(25^\\circ\\text{C}\\)?"
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url: "https://nerd-notes.com/ubq/121468/"
date_modified: "2026-08-23T05:04:43+00:00"
---

# A student prepares a saturated solution of lead(II) iodide by adding solid \(\text{PbI}_2\) to distilled water at \(25^\circ\text{C}\) until excess solid remains at the bottom of the beaker:

\[ \text{PbI}_2(s) \rightleftharpoons \text{Pb}^{2+}(aq) + 2\,\text{I}^-(aq) \]

The value of \(K_{sp}\) for \(\text{PbI}_2\) at \(25^\circ\text{C}\) is \(3.2 \times 10^{-8}\). Assuming no other equilibria occur, what is the concentration of \(\text{I}^-(aq)\) in the saturated solution at \(25^\circ\text{C}\)?

A student prepares a saturated solution of lead(II) iodide by adding solid \(\text{PbI}_2\) to distilled water at \(25^\circ\text{C}\) until excess solid remains at the bottom of the beaker:

\[ \text{PbI}_2(s) \rightleftharpoons \text{Pb}^{2+}(aq) + 2\,\text{I}^-(aq) \]

The value of \(K_{sp}\) for \(\text{PbI}_2\) at \(25^\circ\text{C}\) is \(3.2 \times 10^{-8}\). Assuming no other equilibria occur, what is the concentration of \(\text{I}^-(aq)\) in the saturated solution at \(25^\circ\text{C}\)?

- **A.** \(1.8 \times 10^{-4}\text{ M}\)
- **B.** \(1.0 \times 10^{-3}\text{ M}\)
- **C.** \(2.0 \times 10^{-3}\text{ M}\)
- **D.** \(4.0 \times 10^{-3}\text{ M}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/121468/*