Registration Dossier
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EC number: 230-711-3 | CAS number: 7287-19-6
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:
- 01 Jul 1987 to 02 Jul 1987
- 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
- Dissociating properties:
- yes
- pKa:
- 4.09
- Temp.:
- 20 °C
- Conclusions:
- The test substance has a dissociation constant pKa of 4.09 at 20 °C.
- Executive summary:
The study was performed to evaluate the dissociation constant of the test substance in water according to OECD TG 112 using a spectrophotometric titration method and in compliance with GLP. The test substance revealed to have a dissociation constant pKa of 4.09 at 20 °C.
Reference
Table 2: Results:
Determination at 20°C |
1 |
2 |
3 |
Concentration |
3E-05 M |
3.9E-5 M |
3.7E-5 M |
Wavelength |
260 nm |
262 nm |
258 nm |
Abs. ionized (dI) |
0.471 |
0.593 |
0.616 |
Abs.molecular (dM) |
0.182 |
0.217 |
0.260 |
pKa average |
4.09 |
4.11 |
4.08 |
Std deviation (+ / -) |
0.014 |
0.028 |
0.026 |
n |
10 |
10 |
10 |
Description of key information
pKa of 4.09 at 20 °C, OECD 112, spectrophotometric titration method, Jäkel 1987.
Key value for chemical safety assessment
- pKa at 20°C:
- 4.09
Additional information
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