Magnesium hydroxide (formula Mg (OH) 2) is a chemical inorganic compound, magnesium hydroxide (alkaline earth metal). It belongs to the group of insoluble bases.
Physical properties of magnesium hydroxide
1. Under normal conditions, magnesium hydroxide is a colorless (transparent) crystals having a hexagonal lattice.
2. It decomposes into magnesium oxide (MgO) and water (H2O) at a temperature of three hundred and fifty degrees.
3. It absorbs carbon dioxide (CO2) and water (H2O) from the air, forming the main magnesium carbonate.
4. Practically insoluble in water and soluble in ammonium salts.
5. This is a foundation of medium strength.
6. In nature it is found in the form of a special mineral - brucite.
How to get magnesium hydroxide?
1. This substance can be obtained through the interaction of magnesium salts with various alkalis, for example:
MgCl2 (magnesium chloride) + 2NaOH (sodium hydroxide) = Mg (OH) 2 (precipitated, magnesium hydroxide) + 2NaCl (sodium chloride)
Mg (NO3) 2 (magnesium nitrate) + 2KOH (potassium base) = Mg (OH) 2 (magnesium base, precipitates) + 2KNO3 (potassium nitrate)
2. Also this chemical compound can be obtained by reacting a solution of magnesium chloride (MgCl2) with calcined dolomite (CaO * MgO):
MgCl2 (magnesium chloride) + CaO * MgO (calcined dolomite) + 2H2O (water) = 2Mg (OH) 2 (magnesium base, precipitates) + CaCl2 (calcium chloride)
3. The magnesium base can also be obtained by the interaction of water vapor with metallic magnesium:
Mg (magnesium metal) + 2H2O (water vapor) = Mg (OH) 2 (precipitates) + H2 (hydrogen, as gas)
Chemical properties of magnesium hydroxide:
1. This substance at a temperature of 350 degrees decomposes into magnesium oxide and water. This reaction looks like this:
Mg (OH) 2 (magnesium base) = MgO (magnesium oxide) + 2H2O (water)
2. Interacts with acids. This forms salt and water. Examples:
Mg (OH) 2 (base) + 2HCl (hydrochloric acid) = MgCl2 (magnesium chloride) + 2H2O (water)
Mg (OH) 2 (base) + H2SO4 (sulfuric acid) = MgSO4 (magnesium sulfate) + 2H2O (water)
3. Reacts with acid oxides. The reaction results in salt and water:
Mg (OH) 2 (base) + SO3 (sulfur oxide) = MgSO4 (magnesium sulfate) + H2O (water)
4. Magnesium hydroxide also interacts with concentrated hot alkali solutions. In this case, hydroxomagnesates are formed. Examples:
Mg (OH) 2 + 2NaOH (sodium base) = Na2 (Mg (OH) 4)
Mg (OH) 2 + S (OH) 2 (sulfur base) = Sr (Mg (OH) 4)
Application:
- as a dietary supplement designed to bind sulfur dioxide (SO2). Registered under the sign E528;
- as a focusing agent for wastewater treatment;
- as an additive in various detergents and as a component in toothpastes;
- for refining sugar and for producing magnesium oxide (MgO);
The use of this chemical in the medical industry deserves special attention.
Magnesium hydroxide in medicine
It is a laxative and antacid that can neutralize hydrochloric (hydrochloric, HCl) acid in the stomach and reduce the activity of gastric juice. In this case, the effect of magnesium hydroxide is not accompanied by changes in the CRR and secondary hypersecretion of hydrochloric acid. Also, this substance helps increase peristalsis and other parts of the intestine. Laxative effect occurs after about 2-6 hours.
Indications for use: chronic gastritis with increased and normal secretion, duodenal ulcer and stomach ulcer, discomfort or pain in the epigastrium, heartburn after smoking or drinking coffee or alcohol, constipation.
Contraindications: hypersensitivity to magnesium hydroxide.
It is worth noting that in patients with kidney problems, after applying a magnesium base, hypermagnemia (that is, an excess of magnesium in the body) may develop.
Also, medicine uses magnesium hydroxide, an algeldrate, which is used for stomach ulcers, acute duodenitis, hyperacid gastritis, gastralgia, chronic pancreatitis, heartburn, hyperphosphatemia, putrefactive or fermentative dipepsy. This drug will be contraindicated in patients with hypersensitivity, Alzheimer's disease, during pregnancy or breastfeeding.