What is the chemical equation

The chemical equation of magnesium hydroxide decomposition by heating is: Mg (OH) 2==heating==MgO+H2O

Magnesium hydroxide decomposes at 380 ℃ to produce water vapor and high-temperature resistant solid magnesium oxide, which absorbs a lot of heat during decomposition. According to this property, magnesium hydroxide is added to plastic and other flammable materials to act as a flame retardant. According to the fire extinguishing principle, the reason why magnesium hydroxide is used as a flame retardant is to remove combustibles, isolate oxygen or air, and reduce the temperature of combustibles to below the ignition point.

magnesium hydroxide

Magnesium hydroxide is an inorganic substance with the chemical formula of Mg (OH) 2, white amorphous powder or colorless hexagonal column crystal, soluble in dilute acid and ammonium salt solution, almost insoluble in water, partially ionized in water, and the aqueous solution is weakly alkaline. When heated to 350 ℃, the natural mineral brucite of magnesium hydroxide can be used to make sugar and magnesium oxide.

Magnesium hydroxide is a moderately strong alkali (its solubility is very small, the solution alkalinity is very weak, and sometimes treated as a weak alkali). It is dehydrated and decomposed when heated to 623K (350 ℃): 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 carbonates composed of 5MgO · 4CO2 · xH2O.