Potassium Perchlorate - ACS Reagent Chemicals (ACS Publications)

Feb 28, 2017 - ... provides, in addition to common physical constants, a general description including typical appearance, applications, and aqueous s...
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Monograph pubs.acs.org/doi/book/10.1021/acsreagents

Potassium Perchlorate 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 Potassium Perchlorate 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, Sulfate, Calcium, Sodium, Heavy Metals, and Iron.

KClO4

Formula Wt 138.54

CAS No. 7778-74-7

GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . colorless or white solid Applications . . . . . . . . . . . . . . . . . . . . . . . . oxidizing agent Aqueous solubility . . . . . . . . . . . . . . . . . . . . 1.7 g in 100 mL at 20 °C

SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99.0–100.5% KClO4

Insoluble matter . . . Chloride (Cl) . . . . . Sulfate (SO4) . . . . . Calcium (Ca) . . . . . Sodium (Na) . . . . . . Heavy metals (as Pb) Iron (Fe) . . . . . . . .

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© 2017 American Chemical Society

Maximum Allowable 0.005% 0.003% 0.001% 0.005% 0.02% 5 ppm 5 ppm

A

DOI:10.1021/acsreagents.4299 ACS Reagent Chemicals, Part 4

ACS Reagent Chemicals

Monograph

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

TESTS Assay (By argentimetric titration after decomposition to chloride). Weigh accurately about 0.28 g into a platinum crucible or dish. Add 3 g of sodium carbonate, and heat, gently at first, then to fusion until a clear melt is obtained. Leach with minimal 10% nitric acid, and boil gently to expel carbon dioxide. Cool to room temperature, add 10 mL of aqueous 30% ammonium acetate solution, and titrate with 0.1 N silver nitrate volumetric solution, using dichlorofluorescein indicator solution to a pink end point. One milliliter of 0.1 N silver nitrate corresponds to 0.01385 g of KClO4.

Insoluble Matter [Part 2: Gravimetric Methods; Insoluble Matter]. Use 50 g dissolved in 600 mL of hot water.

Chloride [Part 2: Colorimetry and Turbidimetry; Chloride]. Dissolve 0.33 g in 20 mL of hot water, filter, and cool.

Sulfate Dissolve 40 g in 400 mL of hot water, add 4 mL of hydrochloric acid, and heat the solution to boiling. Add 5 mL of 12% barium chloride reagent solution, digest in a covered beaker on a hot plate (~100 °C) for 2 h, and allow to stand for at least 8 h. Warm to dissolve any potassium perchlorate that may have crystallized. If a precipitate remains, filter, wash thoroughly, and ignite. The weight of the precipitate should not be more than 0.001 g greater than the weight obtained in a complete blank test.

Calcium and Sodium (By flame AAS, [Part 2: Trace and Ultratrace Elemental Analysis; Atomic Absorption Spectroscopy; Analysis; Procedure for Flame AAS]).

For the Determination of Calcium and Sodium

S a m p l e S t o c k S o l u t i o n . Dissolve 5.0 g of sample in water, and dilute to 100 mL in a volumetric flask with water (1 mL = 0.05 g).

For the Determination of Calcium and Sodium

Element

Wavelength (nm)

Sample Wt (g)

Standard Added (mg)

Flame Type*

Background Correction

Ca

422.7

0.50

0.025; 0.05

N/A

No

Na

589.0

0.05

0.01; 0.02

A/A

No

*A/A is air/acetylene; N/A is nitrous oxide/acetylene.

© 2017 American Chemical Society

B

DOI:10.1021/acsreagents.4299 ACS Reagent Chemicals, Part 4

ACS Reagent Chemicals

Monograph

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

Heavy Metals [Part 2: Colorimetry and Turbidimetry; Heavy Metals (as Lead); Procedure for Heavy Metals, Method 1]. Dissolve 3.0 g in hot water, dilute with water to 60 mL, and use 50 mL to prepare the sample solution. For the control, add 0.01 mg of lead ion (Pb) to the remaining 10 mL, and dilute with water to 50 mL.

Iron [Part 2: Colorimetry and Turbidimetry; Iron; Procedure for Iron, Method 1 (Ammonium Thiocyanate)]. Use 2.0 g.

© 2017 American Chemical Society

C

DOI:10.1021/acsreagents.4299 ACS Reagent Chemicals, Part 4