Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Lead Perchlorate Trihydrate 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 Lead Perchlorate Trihydrate provides, in addition to common physical constants, a general description including typical appearance, applications, change in state (approximate), 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, pH of a 5% Solution at 25.0 °C, Insoluble Matter, Chloride, and Iron.
Pb(ClO4)2 • 3H2O
Formula Wt 460.10
CAS No. 13637-76-8
GENERAL DESCRIPTION Typical appearance . . . . . . . . Applications . . . . . . . . . . . . . Change in state (approximate) . Aqueous solubility . . . . . . . . .
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white solid titrant for complexometric titrations melting point, 88 °C very soluble
SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97.0%–102.0% Pb(ClO4)2 · 3H2O pH of a 5% solution at 25.0 °C . . . . . . . . . . . . 3.0–5.0 Maximum Allowable Insoluble matter . . . . . . . . . . . . . . . . . . . . . 0.005% Chloride (Cl) . . . . . . . . . . . . . . . . . . . . . . . 0.01% Iron (Fe) . . . . . . . . . . . . . . . . . . . . . . . . . . 0.001%
© 2017 American Chemical Society
A
DOI:10.1021/acsreagents.4192 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
TESTS Assay (By complexometric titration of lead). While protecting from moisture, weigh accurately about 1.8 g, transfer to a 400 mL beaker, and dissolve in 250 mL of water. Add 15 mL of a hexamethylenetetramine reagent solution and a few milligrams of xylenol orange indicator mixture, and titrate with 0.1 M EDTA volumetric solution to a yellow color. A precipitate that dissolves readily during the titration will form. One milliliter of 0.1 M EDTA corresponds to 0.04602 g of Pb(ClO4)2 · 3H2O.
pH of a 5% Solution at 25.0 °C [Part 2: Direct Electrometric Methods; pH Potentiometry; pH Range; Procedure for pH of a 5% Solution at 25.0 °C].
Insoluble Matter [Part 2: Gravimetric Methods; Insoluble Matter]. Use 20 g dissolved in water.
Chloride [Part 2: Colorimetry and Turbidimetry; Chloride]. Use 1 g in 100 mL, and take a 10 mL aliquot.
Iron [Part 2: Colorimetry and Turbidimetry; Iron; Procedure for Iron, Method 2 (Hydroxylamine and 1,10-Phenanthroline)]. Use 1 g, and filter after addition of hydroxylamine hydrochloride reagent solution. Wash in the funnel and use the filtrate.
© 2017 American Chemical Society
B
DOI:10.1021/acsreagents.4192 ACS Reagent Chemicals, Part 4
