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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 205-634-3 | CAS number: 144-62-7
Melting point / freezing point
Administrative data
Link to relevant study record(s)
- Endpoint:
- melting point/freezing point
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Study performed according well-known techniques but not under GLP
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 102 (Melting point / Melting Range)
- Principles of method if other than guideline:
- Both Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) had been performed in order to obtain complementary information and allowing differentiation between endothermic and exothermic events which have no associated weight loss (e.g., melting and crystallization) and those which involve a weight loss (e.g., degradation).
For Differential Thermal Analysis (DTA), sample was heated from 20°C to 350°C in a closed glass crucible with a heating rate of 3.0 K/min.
For Thermal Gravimetric Analysis (TGA), sample was heated from 20°C to 240°C under inert atmosphere in a open Aluminium Oxide crucible with a heating rate of 3.0 K/min. - GLP compliance:
- not specified
- Type of method:
- thermal analysis
- Sublimation:
- yes
- Subl. temp.:
- > 160 °C
- Remarks on result:
- other: at atmospheric pressure
- Conclusions:
- The apparent melting point of di-hydrated oxalic acid is caused by loss of crystal water starting at 98°C with a maximum at 100°C. The anhydrous form of oxalic acid starts sublimation around 160°C.
Reference
2 endothermic phenomena have been observed belowin DTA:
- The first endothermic reaction started at 98 ºC (with a peak at 100 ºC) and has been attributed to loss of water of di-hydrated oxalic acid; this is has been proven via TGA showing a weight loss of 29% corresponding to water content of di-hydrated oxalic acid
- The second endothermic reaction started atand up to; TGA proved the loss of total remain weight (71%) corresponding to full decomposition of oxalic acid giving off gases and corresponding to sublimation
Description of key information
Key value for chemical safety assessment
- Melting / freezing point at 101 325 Pa:
- 160 °C
Additional information
The substance sublimates at temperature around 160 ºC
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.
