Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Variamine Blue B (N-[p-Methoxyphenyl]-p-phenylenediamine Hydrochloride) 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 Variamine Blue B 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: Suitability as a Complexometric Ion Indicator.
C13H14N2O • HCl
Formula Wt 250.73
CAS No. 3566-44-7
GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . gray-blue solid Applications . . . . . . . . . . . . . . . . . . . . . . . . indicator
SPECIFICATIONS Suitability as a complexometric ion indicator. . . Passes test
TESTS Suitability as a Complexometric Ion Indicator Weigh 0.2 g of sample, and suspend in 20 mL of water. Stir for 5 min. Mix 200 mL of water, 10 mL of 0.1 M EDTA volumetric solution, and 2 mL of 20% hydrochloric acid. Heat the solution to 40–50 °C. Adjust the pH to 2.5 ± 0.2 with 10% sodium acetate reagent solution, using a pH meter. Add 0.2 mL of the sample solution, and titrate with ferric chloride hexahydrate
© 2017 American Chemical Society
A
DOI:10.1021/acsreagents.4420 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
solution (described below). The color change is from bright yellow to burgundy. Add back gradually 0.10 ± 0.05 mL of 0.1 M EDTA in 0.05 mL increments. The color should return to bright yellow.
For the Determination of Suitability as a Complexometric Ion Indicator
F e r r i c C h l o r i d e H e x a h y d r a t e S o l u t i o n . Dissolve 2.5 g of ferric chloride hexahydrate in 100 mL of dilute hydrochloric acid (1:99).
© 2017 American Chemical Society
B
DOI:10.1021/acsreagents.4420 ACS Reagent Chemicals, Part 4
