Magnesium hydroxide is insoluble

Magnesium hydroxide is insoluble. Magnesium hydroxide is insoluble in water and alcohol, but it can be dissolved in acid and ammonium salt solutions. The refractive index of magnesium hydroxide is 1.580. Magnesium hydroxide can decompose into magnesium oxide and water. The reaction endothermic capacity is 10.7 kcal / mol, and it begins to decompose at 340 ℃. The fastest speed is at 430 ℃, and the decomposition ends at 490 ℃. Magnesium hydroxide is a white powdery solid and a precipitate Insoluble in water It can react with acid and is mainly used in rubber, plastic, paint, coating, chemical industry and other industries.
Chemical properties of magnesium hydroxide:

Magnesium hydroxide is a medium strong base (the solubility of magnesium hydroxide is very small, and the solution is weak, sometimes treated as a weak base). When heated to 623k (350 ℃), it is dehydrated and decomposed: Mg (OH) 2 → mgo+h2o, which is easily soluble in acid or ammonium salt solution. Like magnesium oxide, it is easy to absorb carbon dioxide in the air and gradually form basic carbonate composed of 5mgo · 4co2 · xH2O. It decomposes into magnesium oxide and water when it is higher than 350 ℃, but it can be completely dehydrated only when it is above 1800 ℃.