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Physical & Chemical properties

Dissociation constant

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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