Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Xylenol Orange 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
Downloaded by CORNELL UNIV on June 3, 2017 | http://pubs.acs.org Publication Date (Web): February 28, 2017 | doi: 10.1021/acsreagents.4424
ABSTRACT This monograph for Xylenol Orange provides, in addition to common physical constants, a general description including typical appearance and applications. The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Clarity of Solution and Suitability for Zinc Titration.
C31H30N2O13S (free acid) Formula Wt 672.66 C31H28N2Na4O13S (salt) Formula Wt 760.59
CAS No. 1611-35-4 CAS No. 3618-43-7
Note: This standard applies to both the free acid form and the salt form of this reagent.
GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . dark solid Applications . . . . . . . . . . . . . . . . . . . . . . . . indicator
© 2017 American Chemical Society
A
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.4424 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
SPECIFICATIONS Clarity of solution . . . . . . . . . . . . . . . . . . . . Passes test Suitability for zinc titration . . . . . . . . . . . . . . Passes test
TESTS Clarity of Solution
Downloaded by CORNELL UNIV on June 3, 2017 | http://pubs.acs.org Publication Date (Web): February 28, 2017 | doi: 10.1021/acsreagents.4424
If the indicator is the acid form, dissolve 0.1 g in 100 mL of alcohol. If the indicator is a salt form, dissolve 0.1 g in 100 mL of water. Not more than a faint trace of turbidity or insoluble matter should remain. Reserve the solution for the test for suitability for zinc titration.
Suitability for Zinc Titration Dissolve 2.5 g of hexamethylenetetramine in 75 mL of water. Add 3 mL of 10% nitric acid and 1 mL of 0.1% sample solution reserved from the test for clarity of solution. The color should be yellow. Add 0.03 mL of 0.1 M zinc chloride volumetric solution, which should change the color to a magenta purple. Addition of 0.05 mL of 0.1 M volumetric EDTA solution should restore the yellow color.
© 2017 American Chemical Society
B
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.4424 ACS Reagent Chemicals, Part 4
