Registration Dossier
Registration Dossier
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EC number: 207-838-8 | CAS number: 497-19-8
Dissociation constant
Administrative data
Link to relevant study record(s)
Description of key information
Sodium carbonate is very soluble in water.
It dissociates readily into sodium ions (Na+) and carbonate (CO3 2-) ions which form bicarbonate (HCO3-) ions with the water.
The pKa of CO3 2- is 10.33, which means that at a pH of 10.33 both carbonate and bicarbonate are present in equal amounts
Key value for chemical safety assessment
- pKa at 20°C:
- 10.33
Additional information
In water, sodium carbonate dissociates into sodium and carbonate An emission of sodium carbonate to water will result in an increase in alkalinity and a tendency to raise the pH value. The carbonate ions will react with water, resulting in the formation of bicarbonate and hydroxide, until an equilibrium is established
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