Iodine Monochloride - ACS Reagent Chemicals (ACS Publications)

Feb 28, 2017 - This monograph for Iodine Monochloride provides, in addition to common physical constants, a general description including typical ...
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Monograph pubs.acs.org/doi/book/10.1021/acsreagents

Iodine Monochloride 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 Iodine Monochloride provides, in addition to common physical constants, a general description including typical appearance, applications, and change in state (approximate). The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Insoluble Matter and Assay.

ICl

Formula Wt 162.36

CAS No. 7790-99-0

Suitable for use in Wijs solution.

GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . black solid or reddish-brown liquid Applications . . . . . . . . . . . . . . . . . . . . . . . . determining iodine values of fats and oils Change in state (approximate) . . . . . . . . . . . . melting point, α-form (stable), 27 °C; β-form, 14 °C

SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . I/Cl ratio of Wijs solution prepared from reagent must be 1.10 ± 0.1. Insoluble matter . . . . . . . . . . . . . . . . . . . . . ≤0.005%

© 2017 American Chemical Society

A

DOI:10.1021/acsreagents.4176 ACS Reagent Chemicals, Part 4

ACS Reagent Chemicals

Monograph

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

TESTS Insoluble Matter

For the Determination of Insoluble Matter

S t o c k S o l u t i o n . Dissolve 79.3 ± 0.1 g in glacial acetic acid, and dilute to 250 mL with glacial acetic acid. Filter through a tared filtering crucible. Store the solution in a dry, low-actinic glass bottle.

Wash the stock solution filter thoroughly with acetic acid, and dry at 105 °C.

Assay (By selective titration of reducing and oxidizing power). Prepare Wijs solution (1.4–1.5% ICl in acetic acid) by diluting 11.7 ± 0.1 mL of the stock solution with 217 mL of glacial acetic acid. Determine the I/Cl ratio of this solution as follows:

I o d i n e . To 150 mL of saturated chlorine water in a 500 mL conical flask, add some glass beads, and pipette 5 mL of the Wijs solution into the flask. Shake, heat to boiling, and boil briskly for 10 min. Cool, add 30 mL of 2% sulfuric acid and 15 mL of 15% potassium iodide solution, and mix well. Titrate immediately with 0.1 N sodium thiosulfate volumetric solution, adding 3 mL of starch indicator solution near the end point. To t a l H a l o g e n . Transfer 150 mL of freshly boiled water to a dry 500 mL conical flask. Add 15 mL of 15% potassium iodide solution, pipette 20 mL of Wijs solution into the flask, and mix well. Titrate immediately with 0.1 N sodium thiosulfate volumetric solution, adding 3 mL of starch indicator solution near the end point. Calculate the halogen ratio as follows:

where A = volume, in mL, of 0.1 N sodium thiosulfate used to titrate iodine; and B = volume, in mL, of 0.1 N sodium thiosulfate used to titrate total halogen (as iodine).

© 2017 American Chemical Society

B

DOI:10.1021/acsreagents.4176 ACS Reagent Chemicals, Part 4