Six square column crystal magnesium hydroxide is a colorless or white powder, soluble in water and alcohol, soluble in dilute acid and ammonium salt solution, alkaline aqueous solution. In the water solubility is small, as a strong electrolyte. Natural mineral brucite magnesium hydroxide. Can be used for the sugar and magnesium oxide, etc. For comparing rich content of magnesium hydroxide in nature, and its chemical properties and aluminum is close, so users started to use magnesium hydroxide to replace aluminium chloride used in sweet body products.
Magnesium hydroxide is a weak base, heated to 623 k (350 ℃) [5] the dehydration decomposition: Mg (OH) 2 - > MgO style + H2O, soluble in acid or ammonium salt solution. [6] Accurate said pick up 105 ℃ drying after 2 h sample of about 400 mg, into the conical flask. Add lmol/L sulfuric acid 25.0 ml, after being completely dissolved, add methyl red test solution (TS - 149) several drops, with 1 mol/L sodium hydroxide titration of excessive acid. By volume minus 1 mol/L sulfuric acid consumption and take calcium oxide content in the sample (see quality indicators) of 1 mol/L sulfuric acid volume, its difference is equal to take sample of Mg (OH) 2 content in 1 mol/L sulfuric acid volume. Per Ml, 1 mol/L equivalent to 29.16 Mg Mg (OH) 2 or sulfate CaO28.04 Mg