FERROUS AMMONIUM

Ferrous ammonium suifate, Mohr s salt, FeS04 (NH4)2S04 6H2O—0.5N 196 g per liter. Ferrous sulfate, FeS04 7H2O—0.5N 80 g per liter add a few drops of H2SO4. 

Another reducing titrant is ferrous ammonium sulfate, Fe(NH4)2(S04)2 6H2O, in which iron is present in the +2 oxidation state. Solutions of Fe + are normally very susceptible to air oxidation, but when prepared in 0.5 M 1T2S04 the solution may remain stable for as long as a month. Periodic restandardization with K2Cr20y is advisable. The titrant can be used in either a direct titration in which the Fe + is oxidized to Fe +, or an excess of the solution can be added and the quantity of Fe + produced determined by a back titration using a standard solution of Ce + or... 

The purity of ferrous ammonium sulfate is determined by a redox titration with K2Gt207, using the weight of the reagents as the signal in place of volume. 

Iron. As with copper, some dozen or more materials are used as fertilizer Hon sources. These include ferrous and ferric oxides and sulfides and ferrous ammonium phosphate [10101 -60-7] ferrous ammonium sulfate [10045-89-3] frits, and chelates. In many instances, organic chelates are more effective than inorganic materials. Recommended appHcation rates range widely according to both type of micronutrient used and crop. Quantities of Fe range from as low as 0.5 kg/hm as chelates for vegetables to as much as a few hundred kg/hm as ferrous sulfate for some grains. 

Wheieas the BPO—DMA ledox system works well for curing of unsaturated polyester blends, it is not a very effective system for initiating vinyl monomer polymerizations, and therefore it generally is not used in such appHcations (34). However, combinations of amines (eg, DMA) and acyl sulfonyl peroxides (eg, ACSP) are very effective initiator systems at 0°C for high conversion suspension polymerizations of vinyl chloride (35). BPO has also been used in combination with ferrous ammonium sulfate to initiate emulsion polymerizations of vinyl monomers via a redox reaction (36). 

Although gravimetric methods have been used traditionally for the determination of large amounts of tellurium, more accurate and convenient volumetric methods are favored. The oxidation of teUurium(IV) by ceric sulfate in hot sulfuric acid solution in the presence of chromic ion as catalyst affords a convenient volumetric method for the determination of tellurium (32). Selenium(IV) does not interfere if the sulfuric acid is less than 2 N in concentration. Excess ceric sulfate is added, the excess being titrated with ferrous ammonium sulfate using o-phenanthroline ferrous—sulfate as indicator. The ceric sulfate method is best appHed in tellurium-rich materials such as refined tellurium or tellurium compounds. 

Bromide ndIodide. The spectrophotometric determination of trace bromide concentration is based on the bromide catalysis of iodine oxidation to iodate by permanganate in acidic solution. Iodide can also be measured spectrophotometricaHy by selective oxidation to iodine by potassium peroxymonosulfate (KHSO ). The iodine reacts with colorless leucocrystal violet to produce the highly colored leucocrystal violet dye. Greater than 200 mg/L of chloride interferes with the color development. Trace concentrations of iodide are determined by its abiUty to cataly2e ceric ion reduction by arsenous acid. The reduction reaction is stopped at a specific time by the addition of ferrous ammonium sulfate. The ferrous ion is oxidi2ed to ferric ion, which then reacts with thiocyanate to produce a deep red complex. 

Ohio, high carbon ferrochromium is leached with a hot solution of reduced anolyte plus chrome alum mother Hquor and makeup sulfuric acid. The slurry is then cooled to 80°C by the addition of cold mother Hquor from the ferrous ammonium sulfate circuit, and the undissolved soHds, mostiy siHca, are separated by filtration. The chromium in the filtrate is then converted to the nonalum form by conditioning treatment for several hours at elevated temperature. 

Once the green, nonalum modifications of the chromium ion have formed, reversion to the hexaaquo form on cooling is sufficiendy slow that on chilling to 5°C a cmde ferrous ammonium sulfate can be crystallised, removing neady all the iron from the system. This cmde iron salt is treated with makeup ammonium sulfate, heated again to retain the chromium impurities in the green noncrystallisahle form, and then cooled to separate the bulk of the iron as a technical ferrous ammonium sulfate, which is sold for fertiliser and other purposes. The mother Hquor from this crystallisation is returned to the filtration step. 

The state of reduction can be determined by placing 3 drops of the reaction mixture in a test tube containing 5 ml. of a 10% solution of sodium hydroxide and then adding 5 ml. of a freshly prepared saturated solution of ferrous ammonium sul-... 

A simple test for ether peroxides is to add lOmL of the ether to a stoppered cylinder containing ImL of freshly prepared 10% solution of potassium iodide containing a drop of starch indicator. No colour should develop during one minute if free from peroxides. Alternatively, a 1% solution of ferrous ammonium sulfate, O.IM in sulfuric acid and O.OIM in potassium thiocyanate should not increase appreciably in red colour when shaken with two volumes of the ether. 

Allyl acetate [591-87-7] M 100,1, b 103°, d 0.928, 04 1,40488, np 1.4004, Freed from peroxides by standing with crystalline ferrous ammonium sulfate, then washed with 5% NaHC03 followed by saturated CaCl2 soln. Dried with Na2S04 and fractionally distd in an all-glass apparatus. 

AMMONIUM FERROUS SULFATE see FERROUS AMMONIUM SULFATE ... 

Chemical Designations - Synonyms Ammonium ferrous sulfate. Ammonium iron sulfate. Ferrous ammonium sulfate hexahydrate. Iron ammonium sulfate, Mohr s salt Chemical Formula Fe(NH4)j(S04)j 6Hj0. 

Ferrous ammonium sulfate, 68 Ferrous cliloride, 68 Ferrous ferrite, 69 Ferrous salts, 69 Ferrous sulfate, 69 Fesil Group ASA, 196 Fibrous glass, 69... 

A direct attack on the oxazirane ring occurs with ferrous salts. Oxaziranes are decomposed by aqueous solutions of ferrous ammonium sulfate even at room temperature. The reaction follows a radical-chain mechanism because le.ss than stoichiometric amounts of the ferrous salt cause the decomposition, 2-icrt-Butyl-3-phenyloxazirane (9) and 1 equivalent of ferrous salt give ferf-butylbenzamide in 98%... 

Ammonium-ferrisulfat, n. ammonium iron(III). sulfate, ferric ammonium sulfate, -ferro-sulfat, n. ammonium iron(II) sulfate, ferrous ammonium sulfate, -jodat, n. ammonium iodate. -jodid, n. ammonium iodide, -platinchlorid, n. ammonium platinichloride (chloroplatinate). -rest, m. ammonium radical. rhodanid, -rhodantir, n. ammonium thiocyanate, -salpeter, m. ammonium nitrate, -salz, n. ammonium s t. -selfe,/. ammonia soap, -sulfhydrat, n. ammonium hydrosulfide, -sulfocyanid, n. ammonium thiocyanate, -verbindung,/. ammonium compound, -zinn-chlorid, n. ammonium chlorostannate, pink salt. 

Besides Fe-, other reducing agents that may be used in conjunction with H2O2 are aliphatic amines, Na2S203 thiourea, ascorbic acid, glyoxal, sulfuric acid, NaHSOs, sodium nitrite, ferric nitrate, peroxidase, AgNOs, tartaric acid, hydroxylamine, ethylene sulfate, sodium phosphite, formic acid, ferrous ammonium sulphate, acetic acid, ferrous sulphate, and HNO2, etc,... 

Ferroin 175, 365, 381 modification by substituents, 366 prepn. of indicator solution, 175, 365 Ferromanganese analysis of, (ti) 336 Ferrous ammonium sulphate see Ammonium iron(II) sulphate Ferrous iron see Iron(II)... 

A number of methods have been proposed for the detection of rancidity. The determination of active oxygen consists of dissolving the fat in a suitable medium such as chloroform and acetic acid, adding potassium iodide, and titrating the liberated iodine with a standard thiosulfate solution (16, 20). This is perhaps the most widely used method at the present time. Another procedure which has been proposed for the detection of peroxides employs ferrous ammonium sulfate and ammonium thiocyanate in acetone. The resulting red color of ferric thiocyanate is measured spectrophotometrically, and is said by the authors to yield more reproducible results than do the usual titration methods (21). 

Cellulose Chemistry , London (1947), 245—47 22) B.T. Fedoroff, Rapid Method for the Determination of Nitrogen Content of Nitrocellulose by the Ferrous Ammonium Sulphate Method , PACLR 122871 (1948) 23) J. Pearson... 

Ferrous ammonium sulphate Ferrous chloride Ferrous sulphate Lead nitrate Lithium chloride... 

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