Registration Dossier
Registration Dossier
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EC number: 617-298-9 | CAS number: 82097-50-5
Dissociation constant
Administrative data
Link to relevant study record(s)
- Endpoint:
- dissociation constant
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 07 May 1990 to 11 May 1990
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 112 (Dissociation Constants in Water)
- Version / remarks:
- May 1981
- GLP compliance:
- yes (incl. QA statement)
- Dissociating properties:
- yes
- pKa:
- 4.64
- Temp.:
- 20 °C
- Conclusions:
- A dissociation constant (pKa) of 4.64 at at 20 °C was found in water.
- Executive summary:
The study was performed to determine the dissociation constant of the test substance in water. The study was performed in accordance with the OECD TG 112 and GLP principles. A dissociation constant (pKa) of 4.64 at 20 °C was found in water.
Reference
RESULTS
References:
For the reference substances listed in the OECD Test Guideline No. 112 the following pKa values were determined by the method:
| value OECD TG No. 112 | PKa | Temp (°C) |
p-Nitrophenol | 7.15 | 7.14 | 25 |
Benzoic acid | 4.12 | 4.14 | 20 |
p-Chloroaniline | 3.93* | 4.05 | 20 |
* This value in the guideline 112 seems to be incorrect:The standard IUPAC Table (D.D. Perrin, Diss.Constants of Organ. Bases in Aqu. Solution, Butterworths, 1965) lists the following values for 4-Chloroaniline ( p.68)
Description of key information
Dissociation constant: pKa 4.64 at 20 °C, OECD TG 112, spectrophotometric filtration, Jäkal 1990
Key value for chemical safety assessment
- pKa at 20°C:
- 4.64
Additional information
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