Lead, carbonate iodid

M.12 A compound produced as a by-product in an industrial synthesis of polymers was found to contain carbon, hydrogen, and iodine. A combustion analysis of 1.70 g of the compound produced 1.32 g of C02 and 0.631 g of H20. The mass percentage of iodine in the compound was determined by-converting the iodine in a 0.850-g sample of the compound into 2.31 g of lead(II) iodide. What is the empirical formula of the compound Could the compound also contain oxygen Explain your answer. 

Students usually identify the existence of anions such as carbonate, iodide and sul-fate(VI) by adding a barium/silver(I)/lead(II) solution to the unknown, followed by a dilute acid or vice-versa in qualitative analysis practical work sessions and examinations. Mat r students had difficulty understanding the roles of the bar-ium/silver(I)/lead(II) solution and the dilute acid in the tests for anions. For example, 20% believed that the addition of aqueous barium nitrate(V) followed by dilute nitric(V) acid was to test for sulfate(VI) only. Another 25% believed that to test for a carbonate, acid had to be added directly to the unknown sample, while 20% believed that the addition of barium nitrate(V) invalidated the test for carbonates. When the students were asked the purpose of adding dilute nitric(V) acid following die addition of silver nitrate(V) solution (in one question) and lead(II) nitrate(V in another question) to the unknown solutions, 22% and 35%, respectively, indicated... 

HaS or HI, so as to form lead carbonate, sulfide or iodide oidy on the surface without penetration into the crystal (Ref 22). This treatment will unquestionably reduce the efficiency of LA because it will be contaminated by inert materials l)Solubiliry of LA in water or in 50% alcohol was detd as described in item VII F tinder Lead Azide Plant Analytical Procedures In addn to above listed tests, the various LA s were loaded in M47 caps as intermediate chges together with NOLNo 130 as a primary chge and RDX as a base chge and subjected to the following tests given in the Purchase Description PA-PD-202, with Rev 1 dated 30 Sept 1952 and Amend 1 dated 27 Jan 1953 ... 

Lead carbonate and lead iodide are insoluble. Which two soluble salts could you use in the preparation of each substance Write... 

Pigments and dyes provide paint and ink colors. Many highly toxic pigments, such as copper acetate (blue-green), arsenic trisulfide (yellow), and mercury II iodide (red), are no longer used. However, other hazardous pigment compounds, such as lead carbonate, mercury II sulfide, and cadmium sulfide, are still used today. These compounds present a danger to those artists who use their mouths to make a brush more pointed. 

The three methods for lead in air are essentially identical however, one should use S-341 because this method has been validated unlike P CAM 155 or P CAM 173. Although all the methods recommend 2-3 ml of nitric acid for wet ashing, the final solutions differ in that P CAM 155 recommends 1% nitric, P CAM 173 recommends 1% HC1, and S-341 recommends 10% nitric with EDTA 0.1 M to suppress phosphate, carbonate, iodide, fluoride, and acetate ion that cause flame suppression. EDTA is suggested in P CAM 173 where interferences are anticipated. Both S-341 and P CAM 173 use the 217.0 nm line which is twice as sensitive as the 283.3 nm line. Strong nonatomic absorption found when high concentrations of dissolved solid are present requires use of the background corrector. These two methods differ from P CAM 155 and those for biological analysis,... 

HjS or HI, so as to form lead carbonate, sulfide or iodide odly on the surface without penetration into the crystal (Ref 22). This treatment will unquestionably reduce the efficiency of LA because it will be contaminated by inert materials... 

Iron(II) fluoride Iron(II) hydroxide Iron(III) hydroxide Iron(III) phosphate dihydrate Lanthanum iodate Lead(II) bromide Lead(II) carbonate Lead(II) chloride Lead(II) fluoride Lead(II) hydroxide Lead(II) iodate Lead(II) iodide Lead(II) selenate Lead(II) sulfate Lithium carbonate Lithium fluoride Lithium phosphate Magnesium carbonate Magnesium carbonate trihydrate... 

Body fluids are complicated mixtures whose inorganic electrolyte composition in plasma and muscle cells is normally fairly constant, but which may show considerable variations in gastric and pancreatic juices, sweat, saliva and urine. Ion-selective electrodes are the only devices capable of measuring the important normal ions and dissolved gases in fluids and they have proved particularly useful for medical, biochemical and physiological investigations of calcium, potassium, sodium, ammonium, chloride and fluoride. To a lesser extent, the electrodes have been used for bromide, iodide, lead, carbon dioxide, enzymes, proteins and in metal—nucleotide systems. 

Generally, tests for anions involve the formation of precipitates in ionic precipitation reactions with silver nitrate(V), barium nitrate(V)/chloride or lead(ll) nitrate and whether the anions react with acid if they do, a gas is usually evolved and has to be identified. Barium ions form precipitates with carbonate, sulfate(IV) and sulfate(VI) ions, while silver ions form precipitates with chloride, iodide, carbonate and sulfate(IV) ions silver sulfate(VI) is sparingly soluble and a precipitate may not be formed if the concentrations of the reagents used are low. Lead(ll) nitrate(V) is used to determine the presence of iodide and chloride ions. Lead(ll) iodide and lead(ll) chloride precipitates are soluble in hot water (when the mixture is heated) but will recrystallise when cooled (as discussed in section 9.1). The equations for some of these reactions are given overleaf. 

Except for silver iodide which is pale yellow and lead(ll) iodide which is yellow, all the other precipitates are white and need to be differentiated. To determine whether carbonate and sulfate(IV) are present, acid is added to the precipitate. If present, carbonate and sulfate(IV) will react to form carbon dioxide and sulfur dioxide, respectively, and the gas has to be identified. To avoid introducing an additional anion to the test, nitric(V) acid is added when barium nitrate(V), silver nitrate(V) and lead(ll) nitrate(V) are used, and hydrochloric acid is added when barium chloride is used. Sulfuric(VI) acid has to be used with caution as it has an additional disadvantage of forming precipitates with calcium, lead(ll) and barium ions. Figure 9.4 describes how an anion may be identified using barium nitrate(V) or chloride solution. 

Rosingana, M.P. (2009) Gas phase ions generated by laser desorption ionization of silver nitrate, silver iodide, lead (II) oxide, lead (IV) oxide, lead (II, IV) oxide, lead (II) nitrate,lead (II) sulfate, lead (II) carbonate, lead (II) chloride and lead (II) iodide. Master s thesis, Stevens Institute of Technology, Hoboken, NJ. 

Break the sample into small lumps in a mortar (do not grind). Weigh quickly about 5 g in a weighing bottle and wash into a 500-ml volumetric flask containing about 200 ml of water. Add a little lead carbonate to precipitate any sulphides that may be present, dilute to the mark with water, mix thoroughly and filter through a dry filter. Transfer a 50-ml aliquot to a 400-ml beaker, add 200 ml of water, 5 ml of 10 per cent sodium hydroxide solution and a few crystals of potassium iodide. Titrate to a faint opalescence with O IN silver nitrate. 1 ml 0-lN = 0-01302 g KCN. 

Thus, to name just a few examples, a nucleophilic aliphatic substitution such as the reaction of the bromide 3.5 with sodium iodide (Figure 3-21a) can lead to a range of stereochemical products, from a l l mbrture of 3.6 and 3.7 (racemization) to only 3.7 (inversion) depending on the groups a, b, and c that are bonded to the central carbon atom. The ring closure of the 1,3-butadiene, 3.8, to cyclobutene... 

The 2-metalated thiazoles react with a variety of electrophilic substrates in a standard way, leading to addition products with aldehydes, ketones, carbon dioxide, epoxides, nitriles, Schiff bases, and to substitution products with alkyl iodides (12, 13, 437, 440). 

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] ... 

Lithium Iodide. Lithium iodide [10377-51 -2/, Lil, is the most difficult lithium halide to prepare and has few appHcations. Aqueous solutions of the salt can be prepared by carehil neutralization of hydroiodic acid with lithium carbonate or lithium hydroxide. Concentration of the aqueous solution leads successively to the trihydrate [7790-22-9] dihydrate [17023-25-5] and monohydrate [17023-24 ] which melt congmendy at 75, 79, and 130°C, respectively. The anhydrous salt can be obtained by carehil removal of water under vacuum, but because of the strong tendency to oxidize and eliminate iodine which occurs on heating the salt ia air, it is often prepared from reactions of lithium metal or lithium hydride with iodine ia organic solvents. The salt is extremely soluble ia water (62.6 wt % at 25°C) (59) and the solutions have extremely low vapor pressures (60). Lithium iodide is used as an electrolyte ia selected lithium battery appHcations, where it is formed in situ from reaction of lithium metal with iodine. It can also be a component of low melting molten salts and as a catalyst ia aldol condensations. 

Rubidium metal alloys with the other alkaU metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double haUde salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and 2iac. These complexes are generally water iasoluble and not hygroscopic. The soluble mbidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide. 

With Unsaturated Compounds. The reaction of unsaturated organic compounds with carbon monoxide and molecules containing an active hydrogen atom leads to a variety of interesting organic products. The hydroformylation reaction is the most important member of this class of reactions. When the hydroformylation reaction of ethylene takes place in an aqueous medium, diethyl ketone [96-22-0] is obtained as the principal product instead of propionaldehyde [123-38-6] (59). Ethylene, carbon monoxide, and water also yield propionic acid [79-09-4] under mild conditions (448—468 K and 3—7 MPa or 30—70 atm) using cobalt or rhodium catalysts containing bromide or iodide (60,61). 

Note 2. The molar ratios of lead tetraacetate iodine substate are 5.3 1.8 1. These ratios can be lowered and similar results obtained with ratios around 3 1.2 1. Excess iodine and lead tetraacetate react under the influence of light and heat to give methyl iodide and carbon dioxide. 

Fluonnated ylides have also been prepared in such a way that fluonne is incorporated at the carhon P to the carbamonic carbon Vanous fluoroalkyl iodides were heated with tnphenylphosphine in the absence of solvent to form the necessary phosphonium salts Direct deprotonation with butyUithium or hthium dusopropy-lamide did not lead to yhde formation, rather, deprotonation was accomparued by loss of fluonde ion Flowever deprotonation with hydrated potassium carbonate in thoxane was successful and resulted in fluoroolefin yields of45-S0% [59] (equation 54) P-Fluorinated ylides may also be prepared by the reaction of an isopropyli-denetnphenylphosphine yhde with a perfluoroalkanoyl anhydnde The intermediate acyl phosphonium salt can undergo further reaction with methylene tnphenylphosphorane and phenyUithium to form a new yhde, which can then be used in a Wittig olefination procedure [60] (equation 55) or can react with a nucleophile [6/j such as an acetyhde to form a fluonnated enyne [62] (equation 56)... 

Examine the highest-occupied molecular orbital (HOMO of cyanide anion. Is the larger lobe on carbon or nitrogen Would you expect cyanide to act as a carbon or nitrogei nucleophile Does this lead to the lower energy transitioi state (compare the energy of cyanide-l-methyl iodide ( attack and cyanide+methyl iodide N attack) ... 

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