Magnesium hydroxide. Physical and chemical properties. Application.

Magnesium hydroxide (formula Mg (OH) 2) is a chemical inorganic compound, magnesium hydroxide (alkaline earth metal). Refers to the group of insoluble bases.

Physical properties of magnesium hydroxide

1. Under normal magnesium conditions, the hydroxide is a colorless (transparent) crystal having a hexagonal lattice.
2. Decomposes into magnesium oxide (MgO) and water (H2O) at a temperature of three hundred and fifty degrees.
3. Absorbs carbon dioxide (CO2) and water (H2O) from the air, forming the basic magnesium carbonate.
4. Virtually does not dissolve in water and is readily soluble in ammonium salts.
5. This is the basis of medium strength.
6. In nature it occurs in the form of a special mineral - brucite.

How to get magnesium hydroxide?

1. This substance can be obtained by 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 (the base of magnesium precipitates) + 2KNO3 (potassium nitrate)

2. This chemical compound can also be obtained by reaction of a solution of magnesium chloride (MgCl2) with calcined dolomite (CaO * MgO):

MgCl2 (magnesium chloride) + CaO * MgO (calcined dolomite) + 2H2O (water) = 2Mg (OH) 2 (the base of magnesium precipitates) + CaCl2 (calcium chloride)

3. The base of magnesium can also be obtained by the interaction of water vapor with metallic magnesium:

Mg (magnesium metal) + 2H2O (water vapor) = Mg (OH) 2 (precipitated) + H2 (hydrogen, in the form of gas)

Chemical properties of magnesium hydroxide:

1. This substance at a temperature of 350 degrees decomposes into magnesium oxide and water. So this reaction looks like:

Mg (OH) 2 (magnesium base) = MgO (magnesium oxide) + 2H2O (water)

2. Interacts with acids. In this case, salt and water are formed. 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. Interacts with acidic oxides. The reaction produces salt and water:

Mg (OH) 2 (base) + SO3 (sulfur oxide) = MgSO4 (magnesium sulphate) + H2O (water)

4. Also, magnesium hydroxide reacts with concentrated hot alkali solutions. In this case, hydroxo-magnesates 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 food additive designed to bind sulfur dioxide (SO2). Registered under the sign of E528;
- as a foculant for wastewater treatment;
- as an additive to various detergents and as a component in toothpastes;
- for sugar refining and for the production of magnesium oxide (MgO);

Special attention should be paid to the use of this chemical in the medical industry.

Magnesium hydroxide in medicine

This laxative and antacid agent, capable ofneutralize the hydrochloric, hydrochloric, HCl acid in the stomach and reduce the activity of gastric juice. In this case, the action of magnesium hydroxide is not accompanied by changes in the KSCH and secondary hypersecretion of hydrochloric acid. Also, this substance contributes to the increase of peristalsis and other parts of the intestine. The laxative effect occurs approximately in 2-6 hours.

Indications for use: gastritis chronic with increased and normal secretion, ulcer of duodenum and stomach, feeling of discomfort or pain in epigastrium, heartburn after smoking or drinking coffee or alcohol, constipation.

Contraindications: hypersensitivity to magnesium hydroxide.

It is worth noting that in patients who have problems with the kidneys, after the application of the magnesium base, hypermagnes can develop (that is, an excess of magnesium in the body).

Also in medicine magnesiumhydroxide - a remedy that is used for stomach ulcers, acute duodenitis, hyperacid gastritis, gastralgia, chronic pancreatitis, heartburn, hyperphosphatemia, putrefactive or fermentation dyspepsia. This drug will be contraindicated in patients with hypersensitivity, Alzheimer's disease, during pregnancy or breastfeeding.