Ferrous Ammonium Sulfate Reagent

G. Ferrous Ammonium Sulfate Reagent. Dissolve 39.214g of reagent grade Fe(S04).(NH4)2S04.-6H20 in 1 9 sulfuric acid(previously boiled... 

This method can be used for the determination of both free and total active chlorine content in water samples. As mentioned before, the active chlorine reacting with DPD produces a red-colored compoimd. Ferrous ammonium sulfate (Fe(NH4)2(S04)2) reacts with this red compound in a quantitative reaction resulting in a colorless product. So the red compound can be titrated with ferrous ammonium sulfate reagent solution using... 

Procedure 100 cm sample solution, 5 cm DPD reagent solution, and 10 cm buffer solution are mixed together in a titration flask. Immediately following this, the pinkish solution is titrated with ferrous ammonium sulfate reagent solution until the color disappears to measure the free active chlorine content (reagent volume A cm ). At the equivalence, 1 g crystalline potassium iodide is added. If the pinkish color returns, the titration is continued after a 2 min waiting time. The total reagent volume (B cm ) reflects the total free active chlorine content of the sample. 

The homogenized pinkish solution is titrated with ferrous ammonium sulfate reagent solution until the color disappears 1 cm of the titrant added corresponds to 1 mg/1000 cm active chlorine. 

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. 

The combination of Fe2+ and H202, called Fenton s reagent, oxidizes organic material in dilute aqueous solutions. For example, organic components of urine could be destroyed in 30 min at 5()°C to release traces of mercury for analysis.17 To do so, a 50-mL sample was adjusted to pH 3-4 with 0.5 M H2S04. Then 50 xL of saturated aqueous ferrous ammonium sulfate, Fe(NH4)2(S04)2, were added, followed by 100 p,L of 30% H202. 

Reagents Dissolve 2.5 g of ferrous ammonium sulfate in 50 mL of deoxygenated (by boiling) water. Add 0.2 mL of concentrated sulfuric acid and a piece of iron to prevent oxidation of the ferrous ion. Keep the bottle tightly stoppered. The potassium hydroxide solution is prepared by dissolving 5.6 g of potassium hydroxide in 50 mL of methanol. 

In this procedure [3, 12, 13] a known excess of standard ceric ammonium nitrate solution is added to an azide solution or slurry. The excess ceric ammonium nitrate is titrated with standard ferrous ammonium sulfate or sodium oxalate, using ferroin as indicator. The method is extremely simple and flee from hazard once the reagents have been mixed. A serious drawback is that dextrin and polyvinyl alcohol are oxidized by ceric ion. Blay [1] reports gelatin and carboxymethyl cellulose are not oxidized. The method is as follows. 

Standardize the ferrous ammonium sulfate solution against Reagent (b) by introducing from the respective burets approximately 20 cc. of each of these solutions into a beaker containing 100 cc. of H2O. Complete the titration, using Reagent (d) as an outside indicator. From this titration calculate the volume (F) of the ferrous ammonium sulfate solution equivalent to 20 cc. of the dilute and therefore, to 1 cc. of Reagent (a). 

In place of Reagent (b) solution substitute a buret containing the oxidized glycerol with an excess of Reagent (a) and ascertain how many cc. are equivalent to (F) cc. of the ferrous ammonium sulfate solution and, therefore, to i cc. of Reagent (a). Then 250, divided by this last equivalent, = the number of cc. of Reagent (a) present in excess in the 250 cc. flask after oxidation of the glycerol. 

At the reagent bench obtain in a 10-mL or 100-mL graduated cylinder three times the required volume of 0.00070 M Fe + (from ferrous ammonium sulfate) plus a few milliliters in excess. Rinse the appropriate pipet twice with about 1-mL portions of 0.00070 M Fe2+ solution, draining the solution into a beaker for waste liquid. CAUTION Be certain to follow the procedure in Laboratory Methods B very carefully in order to draw liquids into pipets, preferably using a safety pjpet filler. Then measure the requiredvolumeof0.00070MFe2+ solution in triplicate, and drain the portions into separate 25-mL volumetric flasks (Laboratory Methods B) obtained from the equipment bench. Repeat the above procedure to add first 5.0 mL of a pH 4.0 buffer solution, then 1.0 mL of 0.72 M hydroxylamine hydrochloride, NH20H HC1, solution, and finally the appropriate volume of 0.00070 M 1,10-phenanthroline solution to each volumetric flask. what do you observe ... 

The principle of this method is the same as that for the previously described opened reflux (classic) method. In this case, various culture tubes sealed with PTFE caps are used. Sample and the foiu reagents mentioned earlier are placed inside the tubes. Blanks (i.e., reagents with distilled water) are also prepared. All the tubes are mounted on a heating block or placed in an oven at 150°C for 2 h. After this period of time, the excess of dichromate that has not been reduced is determined against a ferrous ammonium sulfate standard solution, using ferroine as indicator. 

Potentiometric Titration of Cr in K2Cr207, Using Ferrous Ammonium Sulfate as Titrant (a) Reagents ... 

Spiral woimd module of 1 m effective separation area of thin film composite (TFC) Polyamide RO membrane was fabricated with the help of Permion-ics Membranes Pvt. Ltd., Vadodara, India, /w-phenylenediamine (MPD) and trimesoyl chloride (TMC) obtained from AVRA Synthesis Pvt. Ltd (Hyderabad, India) were used without further purification. Piperazine was purchased from Sigma-Aldrich, USA. Groimd water samples collected from two different places of Andhra Pradesh (A.P.), India was used for experimental trials. Potassium dichromate, ferrous ammonium sulfate, mercuric sulfate, sulfuric acid, ferroin indicator for COD analysis, sodium thiosulfate, Wrinkler s reagent, MnSO, potassimn iodide, starch indicator for BOD analysis, citric acid, HCl, EDTA, NaOH, and sodium metabisulphite (SMBS) for washing the membranes were purchased from SD Fine Chemicals Ltd., Mumbai, India. Deionized water for cleaning and feed preparation was generated from the same RO system. BOD incubator (RCI-S.NO-313 India), COD incubator... 

These pigments are manufactured by treating ferrous sulfate (FeS04) solutions (sometimes in the presence of ammonium sulfate) with sodium ferrocyanide, giving a white ferrous ferrocyanide, which is then oxidized to ferric ferrocyanide, Fe4[Fe(CN)6], or to Fe(NH4)[Tc(CN)6 by different reagents such as potassium chlorate, bleaching powder, and potassium dichromate. The colloidal pigment is washed and allowed to settle to enhance separation, since filtration of the colloidal solid is difficult. 

Ahmad and Shukla [11] determined primaquine and other antimalarial aminoqui-nolines by vanadium titration. The drugs were determined by oxidation with aqueous ammonium vanadate solution and back titration of the unconsumed reagent with aqueous acidic ammonium ferrous sulfate with V-phenyl anthranilic acid indicator. 

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