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Hydrolysis

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Description of key information

From the available water solubility study it can be concluded that the magnesium oxide and magnesium peroxide present in 10 mg/L of the test substance hydrolyses within 24-48 hours, giving rise to the formation of hydrogen peroxide. The other components of the multi-constituent substance dissociate upon dissolving in the water phase.

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Additional information

The reaction mass of magnesium carbonate and magnesium hydroxide and magnesium oxide and magnesium peroxide will hydrolyze when it comes into contact with water. This property can be clearly demonstrated based on the results of the water solubility study. The water solubility was assessed via the flask method. Mixtures of water and the test substance in concentrations of 10, 100 and 1000 mg/L were stirred for 24, 48 and 96h. Subsequently, quantitative analyses of magnesium and hydrogen peroxide were performed.

The results of this experiment showed that:

 

1) The theoretical maximum concentration of magnesium is obtained within 24-48 hours in the 10 mg/L test solution. As a consequence, the water solubility of the reaction mass of magnesium carbonate and magnesium hydroxide and magnesium oxide and magnesium peroxide is > 0.01 g/L. but less than 0.1 g/L.

 

2) Hydrogen peroxide is being formed when the reaction mass of magnesium carbonate and magnesium hydroxide and magnesium oxide and magnesium peroxide is present in an aqueous environment.

 

In conclusion, in a 10 mg/L solution of the reaction mass of magnesium carbonate and magnesium hydroxide and magnesium oxide and magnesium peroxide in water, the following reactions occur:

* The magnesium peroxide and magnesium oxide hydrolyse within 24-48 hours.

* The magnesium hydroxide and magnesium carbonate are completely dissolved within 48 hours.