Ammonium ferrous sulfate

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. 

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. 

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). 

It is unfortunately the case that when we incubate apoferritin with a certain number of iron atoms (for example as ferrous ammonium sulfate), the product, after elimination of non-protein-bound iron, does not have a homogeneous distribution of iron molecules which were able to (i) take up iron rapidly through the three fold channels, (ii) quickly transfer it and form a diiron centre on a ferroxidase site, and (iii) to transfer the iron inward to a nucleation site, where (iv) it will begin to catalyse iron oxidation on the surface of the growing crystallite, will accumulate iron much more rapidly, and in much greater amounts than molecules in which steps (i), (ii) and (iii) are slower, for whatever reasons (perhaps most importantly subunit composition, and the disposition of subunits of the two types H and L, one with regard to the other). This polydispersity makes the analysis of the process of iron uptake extremely difficult. 

The chemical method for the determination of the chemical oxygen demand of non-saline waters involves oxidation of the organic matter with an excess of standard acidic potassium dichromate in the presence of silver sulfate catalyst followed by estimation of unused dichromate by titration with ferrous ammonium sulfate. Unfortunately, in this method, the high concentrations of sodium chloride present in sea water react with potassium dichromate producing chlorine ... 

Ferrous ammonium sulfate, Mohr s salt, FeS04 (NH4)2S04 6H20—0.5TV 196 g per liter. Ferrous sulfate, FeS04 7H20—0.5TV 80 g per liter add a few drops of H2S04. 

Mohr s salt See ferrous ammonium sulfate. morz, s6lt ... 

The mixture is allowed to warm up over 20 minutes and is poured into a 2-1. separatory funnel. The purplish solution is washed with a saturated ammonium sulfate solution (about 1.5 1.) containing ferrous ammonium sulfate until the rust-brown ferric color is no longer produced. The organic layer is dried over magnesium sulfate and concentrated, leaving a dark solid. Purification of the solid by high-vacuum short path distillation gives 127-142 g. (73-81%) of a pinkish or tan-colored product, b.p. 148-150° (0.15 mm.), m.p. 145-147°. It may be further purified by sublimation, or recrystallization from benzene-hexane, m.p. 148-149°. 

The mixture is tested for peroxide as follows Prepare an approximately 1% solution of ferrous ammonium sulfate. Transfer 5 ml to each of two test tubes and add 0.5 iriL of 0.5 M sulfuric acid and 0.5 iil. of 0.1 M potassium thiocyanate solution to each tube. Add 5 mL of the methylene chloride solution to one of the test tubes and shake well. The aqueous phase in the methylene chloride tube should not develop a brown red color when examined parallel to the blank. 

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