Solubility, lead sulfate

Lehman, T. A. Everett, W. W. Solubility of Lead Sulfate in Water and in Sodium Sulfate Solutions, /. Chem. Educ. 1982, 59, 797. 

Acid Oxidation. Reactions of lead with acid and alkaUes are varied. Nitric acid, the best solvent for lead, forms lead nitrate acetic acid forms soluble lead acetate in the presence of oxygen sulfuric acid forms insoluble lead sulfate. Sulfuric acid is stored in containers with chemical or acid-grade lead. Lead dissolves slowly in HCl, but in the presence of aqueous alkaUes forms soluble plumbites and plumbates. 

Lead shows excellent resistance to phosphoric and sulfuric acid in almost all concentrations and at elevated temperatures, as well as to sulfide, sulfite, and sulfate solutions. The corrosion film is insoluble lead sulfate which rapidly reforms if it is damaged. Lead is also resistant to chlorides, fluorides, and bromates at low concentrations and low temperatures. However, because lead is soluble in nitric and acetic acids, it is not resistant to these acids. 

The carbonates, sulfates, nitrates, and haUdes of lead (except the yeUow iodide) are colodess. Bivalent lead forms a soluble nitrate, chlorate, and acetate a slightly soluble chloride and an insoluble sulfate, carbonate, chromate, phosphate, molybdate, and sulfide. Highly crystalline basic lead salts of both anhydrous and hydrated types are readily formed. Tetrabasic lead sulfate [52732-72-6] 4PbO PbSO, and the hydrated tribasic salt [12397-06-7] ... 

Metals less noble than copper, such as iron, nickel, and lead, dissolve from the anode. The lead precipitates as lead sulfate in the slimes. Other impurities such as arsenic, antimony, and bismuth remain partiy as insoluble compounds in the slimes and partiy as soluble complexes in the electrolyte. Precious metals, such as gold and silver, remain as metals in the anode slimes. The bulk of the slimes consist of particles of copper falling from the anode, and insoluble sulfides, selenides, or teUurides. These slimes are processed further for the recovery of the various constituents. Metals less noble than copper do not deposit but accumulate in solution. This requires periodic purification of the electrolyte to remove nickel sulfate, arsenic, and other impurities. 

The metal salts of MSA are highly soluble in water as well as in some organic solvents, making MSA usefijl in electroplating operations. For example, lead sulfate is insoluble in water, whereas lead methanesulfonate (lead mesylate) is water soluble. 

The charge-discharge reaction of the negative electrode corresponds to curve A in Fig. 1, but the Pb2+ ion activity is now determined by the solubility of lead sulfate (PbS04). Thus Eq. (12) has to be modified into... 

The feasibility of the above reaction ensues from the data on the solubility products of lead sulfate and lead carbonate salts. Evidence abounds that both sulfate and carbonate ions are present. 

As examples of some water-soluble salts, mention may be made of potassium chloride, copper sulfate, and sodium vanadate. As examples of some water-insoluble salts, mention may be made of some typical ones such as lead chloride, silver chloride, lead sulfate, and calcium sulfate. The solubilities of most salts increases with increasing temperature. Some salts possess solubilities that vary very little with temperature or even decline. An interesting example is provided by ferrous sulfate, the water solubility of which increases as temperature is raised from room temperature, remains fairly constant between 57 and 67 °C, and decreases at higher temperatures to below 12 g l-1 at 120 °C. Table 5.2 presents the different types of dissolution reactions in aqueous solutions, and Table 5.3 in an indicative way presents the wide and varied types of raw materials that different leaching systems treat. It will be relevant to have a look at Table 5.4 which captures some of the essential and desirable features for a successful leaching system. 

Many salts and minerals display an enhanced tendency to decompose and dissolve by processes involving complex ion formation and chloride acts as a ligand in these complexes. Lead sulfate has a poor solubility in water. However, in the presence of chloride ions, a complex chloroplumbate ion is formed and thereby solubility is enhanced. The relevant reactions are ... 

Salts such as silver chloride or lead sulfate which are ordinarily called insoluble do have a definite value of solubility in water. This value can be determined from conductance measurements of their saturated solutions. Since a very small amount of solute is present it must be completely dissociated into ions even in a saturated solution so that the equivalent conductivity, KV, is equal to the equivalent conductivity at infinite dilution which according to Kohlrausch s law is the sum of ionic conductances or ionic mobilities (ionic conductances are often referred to as ionic mobilities on account of the dependence of ionic conductances on the velocities at which ions migrate under the influence of an applied emf) ... 

Those who use recreational shooting ranges may be exposed to lead and soluble lead compounds, such as carbonates and sulfates, in soil. Surface... 

Lead sulfate precipitates when an aqueous solution of lead nitrate or other soluble salt of lead is treated with sulfuric acid. 

Zinc also may be produced by electrolysis of zinc sulfate solution. The zinc oxide in the roasted concentrate is leached with sulfuric acid. The oxide is converted to soluble zinc sulfate. Impurity metals, such as iron, copper, cadmium, arsenic, tin, and cobalt are removed by precipitation, floe formation, and other methods. The purified zinc sulfate solution is electrolyzed using aluminum cathodes and lead anodes. Zinc is deposited on the cathode. 

The experimental design consisted of setting up duplicate resin columns for the concentration of 1 L of aqueous solution containing 25 /xg/L of lead as lead nitrate. Two other resin columns were used to test the 25 /xg/L of lead plus 2000 /xg/L of humic substances. One resin blank, which contained no lead or humic substances, was used. The pH of these solutions was adjusted to 6-7. No salts were added because of the possibility of precipitating lead as one of the salts, particularly as lead sulfate, which is known to have a very low solubility in water. One... 

Sulfates. Lead sulfate CAS 7446-l4-2. PbSOj. white precipitate, formed by reaction of soluble lead salt solution and sulfuric acid or sodium sulfate solution basic lead sulfate, "sublimed white lead." white solid, formed 11 > by reaction ol lead sulfate and lead hydroxide in waler Islow reaction , and t2i by roasting galenite in a ennem of air. 

All sulfates are soluble in water except barium, calcium and lead sulfates. 

Most of the lead in soil exists in sparingly soluble forms. When 2784 ppm of lead nitrate were added to soil, it was found that after three days the soluble lead content was only 17 ppm [104]. It is to be expected that all ions will accumulate in nature as their less soluble compounds, such as oxides, carbonates, silicates and sulfates, the relative proportions of each depending on the nature of the soil and on solubility. 

Most sulfate compounds are soluble, except lead sulfate (PbS04) and barium sulfate (BaS04), which are insoluble, and silver sulfate (Ag2S04) and calcium sulfate (CaS04), which are slightly soluble. 

Lead acetate White precipitate of lead sulfate soluble in hot concentrated sulfuric acid, ammonium acetate, ammonium tartrate, and sodium hydroxide... 

The very slight solubilities of lead sulfate, lead oxalate, and lead chromate (chrome yellow) in water serve to remind us of the similarity... 

Sr2+, Ba2+, Ra2+, and Pb2+ are insoluble, but most other sulfate compounds are soluble. Lead(II) iodide is insoluble. 

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