Registration Dossier
Registration Dossier
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EC number: 201-155-9 | CAS number: 78-90-0
Dissociation constant
Administrative data
Link to relevant study record(s)
Description of key information
pKa1 = 9.82 at 25 °C
pKa2 = 6.61 at 25 °C
Key value for chemical safety assessment
Additional information
Several pKa values are available for both dissociation events in the literature. A WoE approach was created for five different literatures. The values are in good agreement.
For the event between the neutral species and the singly-protonated (pKa1) the values are in a range of 9.82 - 10.
For the event between the singly-protonated species and the doubly-protonated (pKa2) the values are in a range of 6.61 - 7.13.
The values of Xiong, Dazhen et al (2013) were choosed as specific values.
The pka values indicate that the molecule will exist primarily as a cation in the environment.
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