Lead chloride solubility

Lead. Hydrochloric acid precipitates from solutions not too dilute, white lead chloride, soluble in hot water. 

A precipitation reaction occurs when two or more soluble species combine to form an insoluble product that we call a precipitate. The most common precipitation reaction is a metathesis reaction, in which two soluble ionic compounds exchange parts. When a solution of lead nitrate is added to a solution of potassium chloride, for example, a precipitate of lead chloride forms. We usually write the balanced reaction as a net ionic equation, in which only the precipitate and those ions involved in the reaction are included. Thus, the precipitation of PbCl2 is written as... 

Although lead chloride is moderately soluble in the acid, lead is also used occasionaUy in hydrochloric acid service. Addition of 6—25% Sb increases the corrosion resistance. AH and ferric chloride accelerate the corrosion. Durichlor (14.5% Si, 3% Mo, 82% Fe), a sUica-based aUoy, shows exceUent resistance to hot hydrochloric acid in the absence of ferric chloride. 

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. 

Lead Chloride. Lead dichloride, PbCl2, forms white, orthorhombic needles some physical properties are given in Table 1. Lead chloride is slightly soluble in dilute hydrochloric acid and ammonia and insoluble in alcohol. It is prepared by the reaction of lead monoxide or basic lead carbonate with hydrochloric acid, or by treating a solution of lead acetate with hydrochloric acid and allowing the precipitate to settle. It easily forms basic chlorides, such as PbCl Pb(OH)2 [15887-88 ] which is known as Pattinson s lead white, an artist s pigment. 

Qualitative. The classic method for the quaUtative determination of silver ia solution is precipitation as silver chloride with dilute nitric acid and chloride ion. The silver chloride can be differentiated from lead or mercurous chlorides, which also may precipitate, by the fact that lead chloride is soluble ia hot water but not ia ammonium hydroxide, whereas mercurous chloride turns black ia ammonium hydroxide. Silver chloride dissolves ia ammonium hydroxide because of the formation of soluble silver—ammonia complexes. A number of selective spot tests (24) iaclude reactions with /)-dimethy1amino-henz1idenerhodanine, ceric ammonium nitrate, or bromopyrogaHol red [16574-43-9]. Silver is detected by x-ray fluorescence and arc-emission spectrometry. Two sensitive arc-emission lines for silver occur at 328.1 and 338.3 nm. 

Lead chloride is freely soluble in hot aqueous solutions, but lead fluoride is almost insoluble in dilute HE solutions. When the HE concentration reaches about 40%, steel is preferred. 

The predictions of the pH/potential diagram are generally fulfilled, but in very concentrated acid solutions, attack may diminish, owing to the relative insolubility of the relevant salt in the acid. Thus, lead nitrate, although soluble in water, has (owing to common ion effect) only slight solubility in concentrated nitric acid, and the corrosion rate is reduced. Similarly, lead chloride is less soluble in moderately concentrated hydrochloric acid than... 

To consider a more complicated example, consider the application of expression (2) to the solubility of lead chloride, PbCl2 ... 

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. 

To conclude this section, reference may be drawn to what is called the Placid process for recycling lead from batteries. Placid denotes the leaching of lead in warm, slightly acidic, hydrochloric acid brine to form soluble lead chloride. Lead is won from the lead chloride on the cathode of an electro winning cell and is collected. Chloride anions are released simultaneously, but then react immediately with hydrogen ions that have been produced stoichio-metrically from electrolysis of water in the anolyte and passed into the catholyte through a membrane. The hydrochloric acid that is formed is returned as a make-up content to the leaching bath. 

Heats of precipitation have been employed to determine the enthalpies of sparingly soluble simple and complex fluorides for example, that of calcium fluoride by adding solid calcium chloride to a solution of excess sodium fluoride saturated with calcium fluoride (88), and of lead chlorofiuoride by adding sodium fluoride solution to a saturated lead chloride solution (50). 

The largest solubility isotope effects are found for sparingly soluble salts. For example, lead chloride and potassium bichromate are 36% and 33.5% more soluble in H20 than D20 at 298.15 and 278.15 K, respectively. For the more soluble salts, NaCl and KC1, the values are 6.4% and 9.0%. Interestingly LiF and LiCl.aq have inverse effects of 13% and 2%, respectively. Recall that lithium salts are commonly designated as structure makers . Almost all other electrolytes are structure breakers . 

A) The reaction that produced the precipitate is Pb (a,) + 2C1 (aq) PbCl2(,). Lead chloride is a slightly soluble salt, with a solubility of 10 g/L at 20°C. The solubility of PbCF increases very rapidly as the temperature rises. At 100°C it has a solubility of 33.5 g/L. However, PbCl2 precipitates very slowly, particularly when other ions that form insoluble chlorides are not present. PbCb dissolves in excess chloride ion as a result of the formation of a complex ion, tetrachloroplumbate(II) ion ... 

The salts of hydrazoic acid, the azides, have solubilities similar to those of the corresponding chlorides. Sodium azide dissolves in water. Silver azide does not dissolve in water or in nitric acid, but dissolves easily in an aqueous solution of ammonia. Lead azide, like lead chloride, is sparingly soluble in cold water but more soluble in hot water it is also soluble in ammonium acetate. 

Waste waters containing low concentrations of soluble organic lead in the presence of high concentrations of other diverse ions such as Cl pose a particularly difficult treatment problem. Generally, organic lead exists in solution as the tri- or dialkyl lead chloride species. These salts are not amenable to the conventional methods used to remove inorganic lead, viz., those of pH adjustment followed by settling. The technique of chemical conversion of the... 

Figures 4 and 5 for Vaq/Vorg = 5.0 show that removal of organic lead corresponds closely to that which would be obtained for a theoretical 1 1 complex in the absence of sodium chloride. Variations in extraction efficiency are observed for different solvents, but for all of the solvents employed a ratio Cr/Cl = 1.0 is sufficient to reduce an initial triethyl lead chloride level of 10 ppm to <1 ppm. A comparison of solvents used suggests an approximate order of effectiveness (corresponding to solubility of the organo-lead complex Hs PbSCSN Hs and also the neutral species Hs PbCl0 in the solvent) of the form shown in Table IV.

All metallic chlorides, except silver chloride and mercurous chloride, are soluble in H.O. but lead chloride, cuprous chloride and thallium chloride are only slightly soluble. Metallic chlorides when heated melt, and volaiilize or decompose, e.g.. sodium chloride, mp 804 (2 calcium, strontium, barium chloride volatilize at red heal magnesium chloride crystals yield magnesium oxide residue and hydrogen chloride cupric chloride yields cuprous chloride and chlorine. Sec also Chlorine Chlorinated Organics. Halides Hypochlorites and Sodium Chloride. 

The solubilities of the azides in general are similar to those of the chlorides. Thus, silver azide is soluble in ammonia water and insoluble in nitric acid. Lead azide, like lead chloride, is sparingly soluble in cold water, but hot water dissolves enough of it so that it crystallizes out when the solution is cooled. One hundred grams of water at 18° dissolve 0.03 gram, at 80° 0.09 gram. 

Most chloride compounds are soluble, except silver chloride (AgCl), lead chloride (PbCl2), and mercury I chloride (Hg2Cl2). 

The lead chloride (PbCl2) precipitate is soluble in hot water, so when the three solids are placed in a hot water bath, the mercury I chloride (Hg2Cl2) and the silver chloride (AgCl) residues remain, and the lead chloride dissolves in hot water. To test for the presence of lead ion in the filtrate, chromate ion, Cr04 2, from K2Cr04, can be added to the filtrate ... 

Lead acetate Potassium dichromate and concentrated sulfuric acid Sodium nitrite Copper sulfate Mercury (II) chloride Yellow precipitate of lead iodide soluble in excess hot water Liberation of iodine Liberation of iodine Brown mixed precipitate Scarlet precipitate of mercury (II) iodide... 

Small Quantities of Soluble Salts. Wear nitrile rubber gloves, laboratory coat, and eye protection. Dissolve the soluble lead salt (0.04 mol, e.g., 11 g of lead chloride) in water (200 mL) and add, while stirring, a solution of sodium metasilicate (Na2Si03-5H20, 25 g,... 

There is nothing new in principle about the use of isotopes as an aid to chemistry. For twenty years the radioactive elements have been used as indicators to study adsorption, solubility, volatility, distribution, and other phenomena of physical chemistry. Distribution of heavy radioactive atoms in plants has been studied through the relative amount of ionization found in the different parts. The ionization theory was supported by dissolving radioactive lead chloride in an aqueous solution of ordinary lead nitrate and then crystallizing out the lead chloride. The radioactive lead was found to be equally distributed between the two salts. In aqueous solution the two different kinds of lead are free to exchange anions, as predicted from the electrolytic dissociation theory. With un-ionized compounds of lead it was found that exchange does not take place. 

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