Registration Dossier

Administrative data

Endpoint:
dissociation constant
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2010-02-03 to 2010-02-11
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Modern study conducted to GLP standards and an approved EU study guideline.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report Date:
2010

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 112 (Dissociation Constants in Water)
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: Liquid
Details on test material:
- Name of test material (as cited in study report): Ammonium xylene sulphonate
- Expiration date of the lot/batch: 31/12/2010 (extended from 31/12/2009)
- Storage condition of test material: Store in original container protected from direct sunlight in a dry cool and well-ventilated area.
- Physical state: Liquid

Results and discussion

Dissociating properties:
not determined
Dissociation constant
pKa:
7.78
Temp.:
20 °C

Any other information on results incl. tables

Full test results:

 Vol. of Titrant (mL)  pH
 0.00  8.18
 0.02  8.14
 0.04  8.11
 0.06  8.05
 0.08  8.00
 0.10  7.95
 0.12  7.93
 0.14  7.88
 0.16  7.78
 0.18  7.69
 0.20  7.58
 0.50  3.34
 1.00  2.53
 2.00  2.10
 3.00  1.90

Applicant's summary and conclusion

Conclusions:
The substance has a pKa value of 7.78.
Executive summary:

The dissociation constant has been determined using OECD method 112. The pKa is found to be 7.78.