The magnesium hydroxide is a metal hydroxide, has basic properties so it is widely used in medicine as antacid .
According to ( IUPAC ) the systematic name is ” magnesium hydroxide “, but it can have other names such as “milk of magnesia” or “magma of magnesia”.
Its chemical formula is Mg (OH) 2 .
Summary
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- 1 Historical Review
- 2 Physical properties
- 3 Structure
- 4 Obtaining
- 5 Applications
- 1 In medicine
- 2 In industry
- 6 Sources
Historical review
Magnesium hydroxide emerged as a fluid preparation of magnesia in 1829 , by James Murray with his own design which was very successful. Then it was propagated as such in Australia being approved by the Royal College of Surgeons in 1838 . His fluid magnesia product was patented two years after his death in 1873 .
The term magnesia milk was first used for a white, aqueous alkaline suspension of magnesium hydroxide formulated by Charles Henry Phillips in 1880 which was sold under the name “Phillips milk of magnesia”. Magnesia ») for medicinal use.
Physical properties
- Aggregation state: solid
- Appearance: white
- Density : 1.04 kg / m3; 0.00104 g / cm3
- Molar mass : 58.3 g / mol
- Melting point : 623 K (350 ° C)
- Solubility in water: 12 mg in 1 L of water
Structure
Magnesium hydroxide is an ionic solid, whose crystalline network is formed by the metal cation Mg 2+ and two hydroxide anions OH – , linked through an ionic bond , and a covalent bond between the oxygen atom and the hydrogen of the ion hydroxide. In aqueous or molten solution, magnesium hydroxide has basic properties and conducts electric current. The presence of hydroxide ions in solution makes it possible to identify them with the indicators: phenolphthalein , litmus and bromothymol blue , acquiring a red and blue coloration, respectively.
Obtaining
Magnesium hydroxide is poorly soluble and is obtained by the direct reaction of a metal hydroxide with a water-soluble salt:
Mgcl 2 (ac) + 2NaOH (ac) = Mg (OH) 2 (s) + 2NaCl (ac) ΔH <0
In special conditions it can be obtained by direct reaction of magnesium oxide with water since it is slightly soluble in it.
Applications
In medicine
Magnesium hydroxide is an antacid used to relieve heartburn (heartburn or heartburn), acid indigestion, and stomach upset. They can be used to treat these symptoms in patients with peptic ulcer , gastritis , esophagitis , hiatal hernia, or too much acid in the stomach (gastric hyperacidity). Combined with the acid of the stomach and neutralize it . Although the side effects of this medication are not common, they could occur. To avoid the lime or plaster flavor , it can be taken with water or milk .
In the industry
Magnesium hydroxide is used as an alternative agent, in the precipitation of heavy metals (Fe, Cu, Zn. And Ni) from a simulated effluent at pH 1, in a batch system. It is used in the refining of sugar , in the extraction of magnesium metal, in the uranium process , and in the sulfite wood pulp process.
