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Feb 28, 2017 - nitrate volumetric solution to a reddish brown color. One milliliter of 0.1 N silver nitrate corresponds to 0.01490 g of. Na2Fe(CN)5NOÂ...
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Monograph pubs.acs.org/doi/book/10.1021/acsreagents

Sodium Nitroferricyanide Dihydrate (Disodium Pentakis(cyano-C)nitrosylferrate(2-) Dihydrate; Sodium Pentacyanonitrosoferrate(III) Dihydrate) Part 4, Monographs for Reagent Chemicals: General Descriptions, Specifications, and Tests eISBN: 9780841230460 Tom Tyner Chair, ACS Committee on Analytical Reagents James Francis Secretary, ACS Committee on Analytical Reagents

ABSTRACT This monograph for Sodium Nitroferricyanide Dihydrate provides, in addition to common physical constants, a general description including typical appearance, applications, and aqueous solubility. The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Assay, Insoluble Matter, Chloride, and Sulfate.

Na2Fe(CN)5NO • 2H2O

Formula Wt 297.95

CAS No. 13755-38-9

GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . ruby-red solid Applications . . . . . . . . . . . . . . . . . . . . . . . . detection of alkali sulfides Aqueous solubility . . . . . . . . . . . . . . . . . . . . 40 g in 100 mL at 20 °C

SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99.0–102.0% Na2Fe(CN)5NO · 2H2O Maximum Allowable Insoluble matter . . . . . . . . . . . . . . . . . . . . . 0.01% Chloride (Cl) . . . . . . . . . . . . . . . . . . . . . . . 0.02% Sulfate (SO4) . . . . . . . . . . . . . . . . . . . . . . . Passes test

© 2017 American Chemical Society

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DOI:10.1021/acsreagents.4358 ACS Reagent Chemicals, Part 4

ACS Reagent Chemicals

Monograph

pubs.acs.org/doi/book/10.1021/acsreagents

TESTS Assay (By argentimetric titration of ferricyanide content). Weigh accurately about 1.5 g, and transfer to a 100 mL volumetric flask with about 80 mL of water. Dilute to the mark, and mix after complete dissolution. To a 25 mL aliquot of this solution in a 250 mL conical flask, add 50 mL of water and 1 mL of 10% potassium chromate reagent solution. Titrate with 0.1 N silver nitrate volumetric solution to a reddish brown color. One milliliter of 0.1 N silver nitrate corresponds to 0.01490 g of Na2Fe(CN)5NO · 2H2O.

Insoluble Matter Dissolve 10 g in 50 mL of water at room temperature, filter promptly through a tared, preconditioned filtering crucible, wash thoroughly, and dry at 105 °C.

Chloride Dissolve 1.0 g in 175 mL of water, add 1.25 g of cupric sulfate crystals dissolved in 25 mL of water, mix thoroughly, and allow to stand until the precipitate has settled. Filter through a chloride-free filter, rejecting the first 50 mL of the filtrate. Dilute 10 mL of the filtrate with water to 20 mL, and add 1 mL of nitric acid and 1 mL of silver nitrate reagent solution. Any turbidity should not exceed that produced by 0.01 mg of chloride ion (Cl) in an equal volume of solution containing the quantities of reagents used in the test, with enough cupric sulfate added to match the color of the test.

Sulfate Dissolve 5.0 g in 100 mL of water without heating, filter, and to the filtrate add 0.25 mL of glacial acetic acid and 5 mL of 12% barium chloride reagent solution. Stir and pour into a Nessler tube for observation. No turbidity should be produced in 10 min. (Limit about 0.01%.)

© 2017 American Chemical Society

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DOI:10.1021/acsreagents.4358 ACS Reagent Chemicals, Part 4