Lead nitrate

Addition of calcium nitrate solution to a fluoride gives a white precipitate of calcium fluoride, CaFj. If the latter is precipitated slowly, it can be filtered off and weighed to estimate the fluoride. Fluoride can also be determined by the addition of sodium chloride and lead nitrate which precipitate lead chlorofluoride, PbClF. This is filtered off and weighed. 

The use of lead nitrate in place of silver nitrate is to be avoided, for the precipitated lead sulphide occludes most of the free acid. 

Pheiiyl iso-thiocyanate may be prepared in quantity directly from aniline. Aniline, carbon disulphide and concentrated aqueous ammonia react to form the sparingly soluble ammonium phenyldithiocarbamate this is decomposed by lead nitrate to produce phenyl iso-thiocyanate ... 

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... 

Ma.nufa.cture. Lead azide is typically made from sodium azide [26628-22-8] in small (eg, 5 kg) batches buffered by the reaction solutions of lead nitrate or lead acetate ... 

PbF2 is readily prepared by the action of hydrogen fluoride on lead hydroxide, lead carbonate, or a-lead oxide. It can also be obtained by precipitation from lead nitrate or lead acetate solutions using potassium fluoride, ammonium fluoride, or ammonium bifluoride. 

Nitrates. Iron(II) nitrate hexahydrate [14013-86-6], Fe(N03)2 6H20, is a green crystalline material prepared by dissolving iron in cold nitric acid that has a specific gravity of less than 1.034 g/cm. Use of denser, more concentrated acid leads to oxidation to iron(III). An alternative method of preparation is the reaction of iron(II) sulfate and barium or lead nitrate. The compound is very soluble in water. Crystallisation at temperatures below — 12°C affords an nonahydrate. Iron(II) nitrate is a useful reagent for the synthesis of other iron-containing compounds and is used as a catalyst for reduction reactions. 

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 Fluoride. Lead difluoiide, Pbp2, is a white oithorhombic salt to about 220°C where it is transformed into the cubic form some physical properties ate given in Table 1. Lead fluoride is soluble in nitric acid and insoluble in acetone and ammonia. It is formed by the action of hydrofluoric acid on lead hydroxide or carbonate, or by the reaction between potassium fluoride and lead nitrate. 

Lead nitrate [10099-74-8] Pb(N02)2, mol wt 331.23, sp gr 4.53, forms cubic or monoclinic colorless crystals. Above 205°C, oxygen and nitrogen dioxide are driven off, and basic lead nitrates are formed. Above 470°C, lead nitrate is decomposed to lead monoxide and Pb O. Lead nitrate is highly soluble in water (56.5 g/100 mL at 20°C 127 g/100 mL at 100°C), soluble in alkalies and ammonia, and fairly soluble in alcohol (8.77 g/100 mL of 43% aqueous ethanol at 22°C). Lead nitrate is readily obtained by dissolving metallic lead, lead monoxide, or lead carbonate in dilute nitric acid. Excess acid prevents the formation of basic nitrates, and the desired lead nitrate can be crystallized by evaporation. 

Lead antimonate [13510-89-9] (Naples yellow), Pb2(Sb0 2> mol wt 993.07, d = 6.58g/cm, is an orange-yeUow powder that is insoluble in water and dilute acids, but very slightly soluble in hydrochloric acid. Lead antimonates are modifiers for ferroelectric lead titanates, pigments in oil-base paints, and colorants for glasses and glazes (see Colorants for ceramics). They are made by the reaction of lead nitrate and potassium antimonate solutions, followed by concentration and crystallization. 

Lead borate moaohydrate [14720-53-7] (lead metaborate), Pb(B02)2 H20, mol wt 310.82, d = 5.6g/cm (anhydrous) is a white crystalline powder. The metaborate loses water of crystallization at 160°C and melts at 500°C. It is iasoluble ia water and alkaHes, but readily soluble ia nitric and hot acetic acid. Lead metaborate may be produced by a fusion of boric acid with lead carbonate or litharge. It also may be formed as a precipitate when a concentrated solution of lead nitrate is mixed with an excess of borax. The oxides of lead and boron are miscible and form clear lead-borate glasses in the range of 21 to 73 mol % PbO. 

Lead chromates are prepared by precipitation techniques from soluble salts ia aqueous media. The raw material Hst iacludes a number of different lead compounds, eg, Htharge, lead nitrate, basic lead acetate, basic lead carbonate, as well as acids, alkahes, sodium bichromate, and sodium chromate. The typical reaction can be represented by the foUowiag equation ... 

Sulfide content is determined by titration with standard lead nitrate solution (1 g/L). The titration is continued until a drop of the test solution on a filter paper ceases to produce a stain with a drop of lead nitrate solution. 

Chlorophenyl isothiocyanate has also been prepared by treating an alcoholic solution of sym-di-/)-chlorophenyl thiourea with iodine/ from ammonium -chloroplienyldithiocarbamate and lead nitrate/ (p. 72), and from the action of thiophosgene with /)-chloroaniline. ... 

The salt is dissolved in 800 cc. of water (Note 3) and transferred to a 5-I. round-bottom flask. To the solution is added with constant stirring a solution of 200 g. of lead nitrate (0.6 mole) in 400 cc. of water. Lead sulfide separates as a heavy brown precipitate which soon turns black. The mixture is then distilled with steam into a receiver containing 5-10 cc. of. i N sulfuric acid as long as any oil comes over (Note 4). About 2-3 1. of distillate is collected. The product is separated from the water and weighs 63-66 g. 

Phenyl isothiocyanate has been prepared from thiocarbanilide by the action of phosphorus pentoxide, hydrochloric acid, iodine, phosphoric acid, acetic anhydride, and nitrous acid. It has also been prepared from ammonium phenyl dithiocarbamate by the action of ethyl chlorocarbonate, copper sulfate lead carbonate, lead nitrate, ferrous sulfate,and zinc sulfate. ... 

Lead nitrate [10099-74-8] M 331.2, m 470°. Ppted twice from hot (60°) cone aqueous soln by adding HNO3. The ppte was sucked dry in a sintered-glass funnel, then transferred to a crystallising dish which was covered by a clock glass and left in an electric oven at 110° for several hours [Beck, Singh and Wynne-Jones Trans Faraday Soc 55 331 1959], After 2 recrystns of ACS grade no metals above 0.001 ppm were detected. 

Bromobenzaldehyde has been prepared by the oxidation of -bromotoluene with chromyl chloride/ by saponification of the acetal from />-bromophenylmagnesium bromide and orthoformic ester/ by the oxidation of ethyl -bromobenzyl ether with nitric acid/ by the oxidation of /j-bromobenzyl bromide with lead nitrate/ and by the hydrolysis of i-bromobenzal bromide in the presence of calcium carbonate. ... 

Guanidine Nitrate (Coll. Vol. i, 293) From ammonium thiocyanate, lead nitrate, and ammonia at 120°. Gockel, Z. angew. Chem. 48, 430 (1935). 

Hydrogen peroxide solutions (8-27.5% by weight) Lead nitrate... 

Gaseous nitrogen dioxide is a brown, paramagnetic, non-flammable, toxic, strongly oxidizing, coiTosive substance shipped in approved, low-pressure steel cylinders. It is prepared in situ by heating lead nitrate ... 

Pf-Br, K3PO4, CH3NO2. This method avoids the use of lead nitrate. ... 

Blei-rhodanid, n, lead thiocyanate, -rohr, n., -rShre, /. lead tube or pipe, -rostprozess, m. lead roasting, -rot, n. red lead, minium, -safran, m. orange lead, -salbe, /. (Pharm.) lead ointment, cerate of lead subacetate, -salpeter, m. lead nitrate, -salz, n. lead salt, specif, lead acetate, -sammler, m. lead accumulator lead storage battery. 

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... 

Before lead in paint was discontinued, lead chromate was a common pigment in yellow paint. A 1.0-L solution is prepared by mixing 0.50 mg of lead nitrate with 0.020 mg of potassium chromate. Will a precipitate form What should [Pb2+] be to just start precipitation ... 

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