Magnesium peroxide is a fine powder peroxide with a white to white-off color.
Magnesium hydroxide, Mg(OH)2, is a white powder produced in large quantities from seawater by the addition of milk of lime (calcium hydroxide).
Magnesium carbonate, MgCO3, occurs in nature as the mineral magnesite and is an important source of elemental magnesium. It can be produced artificially by the action of carbon dioxide on a variety of magnesium compounds.
Magnesium bicarbonate + Lime → Calcium carbonate + Magnesium carbonate + Water
Mg(HCO3)2 + Ca(OH)2 → CaCO3 + MgCO3 + 2H2O
The action of hydrochloric acid on magnesium hydroxide produces magnesium chloride, MgCl2, a colourless, deliquescent (water-absorbing) substance employed in magnesium metal production, in the manufacture of a cement for heavy-duty flooring, and as an additive in textile manufacture.
Magnesium sulfate, MgSO-4, is a colourless, crystalline substance formed by the reaction of magnesium hydroxide with sulfur dioxide and air.