## Abstract

The stability constants for the formation of lead (Pb^{2+}) with chloridePb^{2 +} + n Cl^{-} ↔ PbCl_{n}^{2 - n} β_{n} (n = 1, 2, 3)have been determined using a spectrophotometric method in NaClO_{4} solutions as a function of ionic strength (0-6 m) and temperature (15-45 °C). The results have been fitted to the equations:{Mathematical expression}with standard errors of 0.05, 0.04 and 0.06, respectively. The thermodynamic values of log β_{1}, log β_{2} and log β_{3} at 25.0 °C and the enthalpies of formation of PbCl^{+}, PbCl_{2}^{0} and PbCl_{3}^{-} are in good agreement with literature values. We have combined our results with the earlier work of [Seward, T.M., 1984. The formation of lead (II) chloride complexes to 300 °C: a spectrophotometric study. Geochim. Cosmochim. Acta 48, 121-134.] Seward (1984) to yield thermodynamic constants that are valid from 15 to 300 °C:(log β_{1} =, 44.82 + 0.031 T - 21.21 log T; log β_{2} =, 61.42 + 0.046 T - 29.51 log T; log β_{3} =, 107.97 + 0.071 T - 51.46 log T)with standard errors of 0.05, 0.08 and 0.10, respectively.

Original language | English (US) |
---|---|

Pages (from-to) | 326-334 |

Number of pages | 9 |

Journal | Geochimica et Cosmochimica Acta |

Volume | 71 |

Issue number | 2 |

DOIs | |

State | Published - Jan 15 2007 |

## ASJC Scopus subject areas

- Geochemistry and Petrology