Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Dissociation constant

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
dissociation constant
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
key study
Study period:
08 February 1996 to 14 February 1996
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
comparable to guideline study
Qualifier:
no guideline followed
Principles of method if other than guideline:
Calculation
GLP compliance:
no
Specific details on test material used for the study:
Name: FAT 40549/A
Batch No: TV 1
Colour: yellow-brown
Aggregate State at room temp: Solid
Stability in Solvent: in water: 48 hours
Stability at storage conditions: Stable
Molecular Weight: 1138 g/mol (free acid)
Analysis: HPLC
Storage: At room temperature
Expiration Date : January 01, 2001
Dissociating properties:
yes
No.:
#1
pKa:
-6
Remarks on result:
other: Ar-SO3H
No.:
#2
pKa:
-5.8
Remarks on result:
other: AR-SO3H
No.:
#3
pKa:
-5.1
Remarks on result:
other: AR-SO3H
No.:
#4
pKa:
-3.3
Remarks on result:
other: AR-SO3H
No.:
#5
pKa:
-0.5
Remarks on result:
other: R-O-SO3H
No.:
#6
pKa:
6.9
Remarks on result:
other: R-CONH2
No.:
#7
pKa:
16.8
Remarks on result:
other: AR-NHCO-R

The pKa values predicted for FAT 40549/A show that the reaction center No. 1 to 5 will be completely dissociated. The pKa values for No. 6 and 7 were estimated to be in the range from 6.9 to 16.8, which is of practical interest for the environment.

Conclusions:
The acid dissociation constant of FAT 40945/A was determined to be in the range from pKa -6.0 to 16.8.
Executive summary:

The molecular structure of the free acid of FAT 40549/A was used for the estimation of the dissociation behaviour. 7 acidic protons (reaction centers) were found in this molecular structure. The order of the reaction center in which the protons are lost was defined to make an acceptable prediction.

The pKa-values predicted for FAT 40549/A show that the reaction center no. 1 to 5 will be completely dissociated. The pKa-values of the reaction center no. 6 and 7 were estimated to be in the range from pKa 6.9 to pKa 16.8, which is of practical interest for the environment. Thus, FAT 40549 will be completely dissociated at environmentally relevant pH conditions.

In conclusion, the acid dissociation constants of FAT 40549/A was evaluated to be in the range from pKa -6.0 to pKa 16.8. Thereby it can be stated that the pKa-values < 3 show no relevant effects on the environment.

Description of key information

The acid dissociation constant of FAT 40549/A was determined to be between -6.0 to 16.8

Key value for chemical safety assessment

pKa at 20°C:
16.8

Additional information

The molecular structure of the free acid of FAT 40549/A was used for the estimation of the dissociation behaviour. 7 acidic protons (reaction centers) were found in this molecular structure. The order of the reaction center in which the protons are lost was defined to make an acceptable prediction.

The pKa-values predicted for FAT 40549/A show that the reaction center no. 1 to 5 will be completely dissociated. The pKa-values of the reaction center no. 6 and 7 were estimated to be in the range from pKa 6.9 to pKa 16.8, which is of practical interest for the environment. Thus, FAT 40549 will be completely dissociated at environmentally relevant pH conditions.

In conclusion, the acid dissociation constants of FAT 40549/A was evaluated to be in the range from pKa -6.0 to pKa 16.8. Thereby it can be stated that the pKa-values < 3 show no relevant effects on the environment.