E. Andres et al., CHARACTERIZATION OF PRECIPITATES FORMED FROM THE TETRAIODOMERCURATE RATE(II) ANION AND MERCURY(I) OR SILVER(I) CATIONS, Journal of the Chemical Society. Faraday transactions, 91(8), 1995, pp. 1217-1221
Citations number
13
Categorie Soggetti
Chemistry Physical","Physics, Atomic, Molecular & Chemical
The nature of precipitates formed from Hg-I or Ag-I and the complex an
ion (HgI4)(2-) has been elucidated by means of X-ray diffraction (XRD)
, scanning electron microscopy (SEM) and energy-dispersive X-ray micro
analysis (EDX). In the case of Hg-I, well crystallized tetragonal Hg2I
2 is formed at the beginning of the precipitation from free I- ions. L
ater, HgI2 precipitates in the form of filamentous masses. On the othe
r hand, Ag-I gives rise first to the formation of hexagonal crystals o
f AgI and, in a further stage, Ag-2(HgI4) also precipitates. On adding
an excess of tetraiodomercurate(II) solution, AgI is dissolved while
filamentous HgI2 precipitates. These results are rationalized, taking
into account the various precipitation and complex formation equilibri
a involved.