FeCl2-HCl

Sa.lts Salting out metal chlorides from aqueous solutions by the common ion effect upon addition of HCl is utilized in many practical apphcations. Typical data for ferrous chloride [13478-10-9] FeCl2, potassium chloride [7447-40-7] KCl, and NaCl are shown in Table 9. The properties of the FeCl2-HCL-H2 0 system are important to the steel-pickling industry (see Metal SURFACE TREATMENTS Steel). Other metal chlorides that are salted out by the addition of hydrogen chloride to aqueous solutions include those of magnesium, strontium, and barium. 

To use the ECES system, activity coefficient data for FeCl2 had to be developed. A recent paper by Susarev et al (15) presented experimental results of the vapor pressure of water over ferrous chloride solutions for temperatures from 25 to 100°C and concentrations of 1 to 4.84 molal. This data was entered into the ECES system in the Data Preparation Block with a routine VAPOR designed to regress such data and develop the interaction coefficients B, C, D of our model. These results replaced an earlier entry which was based on more limited data. All other data for studying the equilibria in the FeCl2-HCl-H20 system was already contained within the ECES system. 

Fig. 8-8. Electron spin resonance spectra of Mn(n) in the filtrates after reaction at pH 5.0 (a) cryptomelane-FeCl2-NH40H system, Mn/Fe molar ratio = 1, (b) cryptomelane-H2O-NH4OH system, (c) Hausmannite-FeCl2-HCl system, Mn/Fe molar ratio = 1, and (d) Hausmannite-H2O-HCl system (Krishnamurti and Huang, 1988).

What is the concentration of Fe + in an electrochemical cell similar to that shown in Example 11.1 if the concentration of HCl in the left-hand cell is 1.0 M, the concentration of FeCl2 in the right-hand cell is 0.0151 M and the measured potential is -1-0.546 V ... 

Different reactions (anodic and cathodic) can occur simultaneously at an electrode, even when there is no net current flow. In Section 2.5.1 we mentioned the example of an iron electrode in HCl + FeCl2 solution where anodic iron dissolution (2.24) and cathodic hydrogen evolution (2.25) occur simultaneously these are the reactions of spontaneous dissolution of iron not requiring a net current. 

For convenience within ECES the ferrous species is designated FEII while the ferric species is designated FEIII, which at times results in having up to four i s in a row. In testing the ECES model, solubility data of FeCl2-2H20 as a function of HCL concentration were available in a paper by Schemmel (16). 

KMgCl3 6H2 O (cr) 54 MgC03-3H20(cr) 69 HCl-3H20(cr) 84 FeCl2-4H20(cr)... 

If 45.0 mol of FeCl2 and 17.0 mol of KMn04 are mixed with excess HCl, how many moles of MnCL can be formed ... 

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