Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Administrative data

Endpoint:
dissociation constant
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
other information
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Accepted calculation method

Data source

Reference
Reference Type:
other: SPARC calculation
Title:
Unnamed
Year:
2011
Report date:
2011

Materials and methods

Principles of method if other than guideline:
Calculation of pKa using SPARC v4.5
GLP compliance:
no

Test material

Constituent 1
Reference substance name:
Isobutyric acid
EC Number:
201-195-7
EC Name:
Isobutyric acid
Cas Number:
79-31-2
IUPAC Name:
2-methylpropanoic acid
Details on test material:
- Smiles notation (if other than submission substance): O=C(O)C(C)C

Results and discussion

Dissociation constant
No.:
#1
pKa:
4.72
Temp.:
25 °C
Remarks on result:
other: macroscopic pKa

Any other information on results incl. tables

Two species:

1: O=C(O)C(C)C

2: O=C([O-1])C(C)C

The macroscopic pKa estimates were generated from the crossing of the charge curves. All species curves of the same charge were summed and the crossing of these curves was taken as an estimate of the macroscopic pKa's.

Applicant's summary and conclusion