PbCl2 LEAD CHLORIDE

PbCl2 LEAD CHLORIDE 178.2156 -1.8711E+04 -5.7943E+01 1.8346E-02... 

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 ... 

PbCl2 LEAD CHLORIDE 60.760 4.1535E-02 1.4883E-14 -1.9009E-17 8.8300E-21 298 768 solid... 

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... 

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. 

The desilverized alloy now contains bismuth as well as lead and ziac. To remove the lead and ziac, advantage is taken of the fact that ziac and lead chlorides are formed before bismuth chloride [7787-60-2J, BiCl, when the alloy is treated at 500°C with chlorine gas. Ziac chloride [7646-85-7] ZnCl, forms first, and after its removal lead chloride [7758-95-4], PbCl2, forms preferentially. This process is continued until the desired level of lead removal has been reached. The bismuth is given a final oxidation with air and caustic soda the refined product has a purity of 99.999%. 

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

The solid is essentially ionic, made up of Pb2 + and Cl ions. The vapour contains bent molecules of PbCl2 (cf. SnCl2). Lead chloride is precipitated when hydrochloric acid (or a solution of a chloride) is added to a cold solution of a lead(II) salt. It dissolves in hot water but on cooling, is slowly precipitated in crystalline form. It dissolves in excess of concentrated hydrochloric acid to give the acid H2[Pb"Cl4]. 

At ordinary temperatures lead chloride does not absorb ammonia, but if cooled to —78° C. and saturated with liquid ammonia, the salt increases to about five times its volume, yielding a white powder of composition PbCl2.8NH3. On raising the temperature loss of ammonia occurs, with the production of lower ammines. 

N. A. E. Millon 4 found that when lead dioxide, Pb02, is added to well-cooled and cone, hydrochloric acid, but little chlorine is evolved, while lead chloride, PbCl2, and a yellow liquid are formed. The liquid slowly evolves chlorine and contains lead in soln. Lead dioxide is precipitated when water is added to the yellow liquid. It was therefore assumed that the liquid contains lead perchloride, PbCl4, in soln. and A. Guyard supposed that a soln. of iodine in potassium iodide contained potassium di-iodide, KI2, because this soln. gives lead tetraiodide, Pbl4, when treated with a lead salt. 

PbCl2 NH4C1 (c). Bronsted8 determined, from electromotive force measurements, the heat of formation of this substance from solid lead chloride and solid ammonium chloride to be 0.35. 

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 ... 

The following reaction can be used to obtain lead(II) chloride, PbCl2. Lead(II) chloride is moderately soluble in warm water. 

Group reaction white precipitate of lead chloride PbCl2, mercury chloride Hg2Cl2, and silver chloride AgCl. 

IV.14 CHLORIDES, Cl- Solubility Most chlorides are soluble in water. Mercury(I) chloride, Hg2Cl2, silver chloride, AgCl, lead chloride, PbCl2 (this is sparingly soluble in cold but readily soluble in boiling water), copper(I) chloride, CuCl, bismuth oxychloride, BiOCl, antimony oxychloride, SbOCl, and mercury(II) oxychloride, Hg2OCl2, are insoluble in water. 

Lead acetate solution white precipitate of lead chloride, PbCl2, from concentrated solutions (see under Lead, Section III.4, reaction 1) ... 

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