Ferrous acid sulphate

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,... 

Ferrous ammonium sulphate, approximately 0.4 M - carefully add 5 ml sulphuric acid (98% m/m H SO ) to 1.5 I water, stir slowly to dissolve, then add 314 g ammonium ferrous sulphate [(NH4)2S04.FeS04.6H20, mol. wt 392.14] stir to dissolve and dilute to 2 I. 

If the standardization titration was 26 ml ferrous ammonium sulphate solution, it had reacted with 25 ml acid-dichromate containing 1.668 mmol. If the back-titration of the residual acid-dichromate was 10 ml ferrous ammonium sulphate solution, then the residual acid-dichromate amounted to 10 x 1.668/26 = 0.642 mmol. The amount used to oxidize the organic carbon is therefore... 

A recent report by Lovenberg and McCarthy 170) showed that in the presence of two-mercaptoethanol, sodium sulfide, and ferrous amonium sulphate, bovine serum albmnin will bind from 8 to 10 atoms of iron per mole of protein and an equivalent amount of acid labile sulfur. The optical spectrum of this compound is similar to that for the non-heme iron proteins. However, no biological or chemical reactivity related to ferredoxin has been observed. 

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

Ferric Salts,—The solution of 1 gm. of powdered ferrous ammonium sulphate in 20 cc. of boiled and cooled water (freed from oxygen), with 1 cc. of hydrochloric acid, should not afford an immediate red color on adding a few drops of potassium sulphocyanate solution. 

Copper, Zinc, and Alkali Salts. — Dissolve 5 gm. of ferrous ammonium sulphate in 50 cc. of water, add 5 cc. of nitric acid (sp. gr. 1.3), and boil the solution for a few minutes then add to the liquid 15 cc. of ammonia water, let stand for about one hour, and filter. The filtrate must be colorless (copper). 

Quantitative Determination. — Dissolve 1 gm. of ferrous ammonium sulphate in 50 cc. of well-boiled and cooled water, add 10 cc. of dilute sulphuric acid, and titrate with decinormal potassium permanganate solution. 

The conditions under which the formation of the arsenides Fe3As and Fe5As4 may occur are indicated on p. 65. The former was obtained by Brakl 1 as a black precipitate by the action of arsine on an alcoholic solution of ferrous ammonium sulphate. The product was only slightly attacked by concentrated hydrochloric or sulphuric acid but was soluble in nitric acid, aqua regia and bromine water. 

Standardisation.—3-5 gms. of pure ferrous ammonium sulphate are dissolved in distilled water, 100 c.cs. of 5N sulphuric acid added, and the whole made up to 250 c.cs. 25 c.cs. of this are oxidised with potassium... 

T. Curtius and J. Rissom showed that the evaporation of a soln. of manganese carbonate in hydrazoic acid gives a pulverulent, non-crystalline manganese hydroxyazide, Mn(OH)(N3)2, which cannot be purified by re-crystallization. The product is sparingly soluble in water it does not explode by percussion, but does so on a hot plate. L. Wohler and F. Martin gave 203° for the explosion temp, of manganese azide. T. Curtius and J. Rissom obtained a colourless soln. of ferrous azide by the action of sodium azide on a soln. of ferrous ammonium sulphate when boiled, the salt decomposes and when shaken in air, a blood-red soln. of ferric azide is formed. The same salt can also be obtained directly from ferric salts. When the soln. of ferric azide is boiled, ferric hydroxide is precipitated and, added T. Curtius and A. Darapsky, if allowed to stand in... 

Absorption of iron by the individual varies with age, iron status, the amount and chemical form of the iron ingested, and with conditions in the gastrointestinal tract, only about 5—15% of iron in the diet being normally absorbed. Ferrous iron, as the sulphate, gluconate, fumarate or lactate or as ferrous ammonium sulphate, is appreciably taken up into the bloodstream from the duodenum, especially in the presence of ascorbic acid, a reducing agent. Little difference was found in the extent of their absorption between ferrous sulphate and the various chelates, but ferric ammonium citrate or polysaccharide complexes were only very poorly absorbed22)... 

Experiment Prepare a solution of a ferrous salt by dissolving 2 grams of ferrous ammonium sulphate in 20 cc. of water, adding a little dilute sulphuric acid and a piece of iron wire. Test both this solution and a solution of a ferric salt (nitrate or chloride) with potassium ferrocyanide, potassium ferricyanide, and potassium sulphocyanate. Tabulate the results. These constitute the standard tests for ferrous and ferric salts. Write equation. 

The acid sulphate, FeS04.5H2S04.5H20,2 is obtained when excess of sulphuric acid is added to a concentrated solution of ferrous sulphate. It yields iridescent crystals, with a brilliant lustre, but which are unstable, decomposing at 95° to 97° C. into the monohydrate. Thus —... 

The salt may be prepared artificially by allowing a mixture of powdered ferrous sulphate and acid ferric sulphate to remain in contact with moist air for several months. It is then obtained as a reddish brown, crystalline powder.2 It decomposes in moist air, yielding ferrous and ferric sulphates, the latter giving a-copiapite and the acid sulphate. 

This method is suitable for almost all azo dyes and some other water-soluble dyes. The titration should be conducted in a well-ventilated fume hood. A dye sample is dissolved in a hydrochloric acid solution. An excess amount of titanous chloride solution is added into the boiling acidic dye solution under the protection of a CO, atmosphere. A back titration is then conducted using a standardised ferrous ammonium sulphate solution with ammonium thiocyanate as the indicator. The titanous chloride solution should be freshly standardised. 

Ammonium ferrous sulfate Ammonium iron sulfate Ammonium iron sulfate (2 2 1) Ammonium iron(ll) sulfate Caswell No. 459B Diammonium ferrous sulfate Diammonium iron bis(sulphate) Diammonium iron sulfate EINECS 233-151-8 EPA Pesticide Chemical Code 050506 Ferroammonsulfat Ferrous ammonium sulfate Ferrous ammonium sulphate Ferrous diammonium disulfate HSDB 456 Mohr s salt Mohr sches salz Sulfuric acid, ammonium iron(2+) salt (2 2 1) Vitaferro Diammonium iron bis(sulphate) EPA Pesticide Chemical Code 060506 Ferrous ammonium sulfate Ferrous ammonium sulphate Ferrous diammonium disulfate HSDB 456 Mohr s salt Sulfuric acid. 

Materials Solutions of ferrous ammonium sulphate, of potassium dichromate, of potassium ferrocyanide, of potassium ferricyanide potassium dichromate, oxalic acid. 

Directions a) To 5 c.c. of ferrous ammonium sulphate solution add potassium permanganate solution very slowly, a few drops at a time toward the end, until a slight excess is present, as indicated by the color of the solution. (1) What is the precipitate (2) Write hypothetical equations, similar to those written for potassium dichromate in Experiment 145, to show the composition of potassium permanganate as being potassium oxide and an acid anhydride, and to show the reduction of the anhydride as it occurs in alkaline or neutral solution. (3) Write equations for the remainder of the hypothetical steps in the oxidation of the ferrous salt and combine them into a single equation for the reaction. 

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