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EC number: 939-464-2 | CAS number: 121617-08-1
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:
- 06/06/2017
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 112 (Dissociation Constants in Water)
- GLP compliance:
- no
- Specific details on test material used for the study:
- Trade name: Marlopon AT 50
Lot No.: 983
Reference No.: 0648 11 00500 - Dissociating properties:
- yes
- No.:
- #1
- pKa:
- 2.19
- Temp.:
- 20 °C
- Conclusions:
- The dissociaiton constant is 2.19.
- Executive summary:
In an OECD guideline study (OECD 112), the dissociation of Marlopon AT 50 has been investigated. The dissociation constant is found to be 2.19.
Reference
| Salt concentration of solution (g/l) | Molarity of solution (mole/l) | Molar conductivity (µS/cm/mole) |
Degree of dissociation (α) |
Dissociation constant |
|||
Solution 5 |
3.4159 |
0.00725 |
44258 |
0.65 |
0.0085 |
||
Solution 6 |
1.7080 |
0.00363 |
49551 |
0.72 |
0.0068 |
||
Solution 7 |
0.8540 |
0.00181 |
56724 |
0.83 |
0.0072 |
||
Solution 8 |
0.4270 |
0.00091 |
60736 |
0.89 |
0.0062 |
||
Solution 9 |
0.2135 |
0.00045 |
61711 |
0.90 |
0.0036 |
||
Average dissociaiton constant = 0.0065
Standard deviation of dissociation constant = 0.0018
pKc = 2.19
Description of key information
In a OECD guideline study (OECD 112) the dissociation constant has been measured. The pKa is 2.19.
Key value for chemical safety assessment
- pKa at 20°C:
- 2.19
Additional information
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