Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 205-503-0 | CAS number: 141-82-2
Dissociation constant
Administrative data
Link to relevant study record(s)
- Endpoint:
- dissociation constant
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Justification for type of information:
- Peer reviewed publication
- Qualifier:
- no guideline followed
- Version / remarks:
- Research methods
- Principles of method if other than guideline:
- The first and second molal dissociation quotients of malonic acid were measured potentiometrically in a concentration cell fitted with hydrogenelectrodes. The hydrogen ion molality of malonic acidJbimalonate solutions was measured relative to a standard aqueous HCI solution from 0 to100°C over 25° intervals at five ionic strengths ranging from 0.1 to 5.0 molal (NaCl).
- GLP compliance:
- no
- Dissociating properties:
- yes
- No.:
- #1
- pKa:
- ca. 2.8
- Temp.:
- 25 °C
- No.:
- #2
- pKa:
- ca. 5.7
- Temp.:
- 25 °C
- Conclusions:
- When compared with oxalic and succinic acids, the dissociation constants follow a predicted trend with the lowest molecular weight member of the group being the strongest acid.
Reference
Description of key information
When compared with oxalic and succinic acids, the dissociation constants follow a predicted trend with the lowest molecular weight member of the group being the strongest acid.
Key value for chemical safety assessment
Additional information
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
