Learn About the preparation of Magnesium Hydroxide

Magnesium hydroxide was made by constantly pumping two aqueous solutions of MgCl2 and NaOH into the reactor chamber, where they reacted to generate Mg(OH)2.

The impacts of several operating variables on the size of magnesium hydroxide nanoparticles were explored,including rotation speed,reactant concentration, and liquid flow rate of the reactants. As the flow rate increased, the particle size of magnesium hydroxide increased as well,but stayed relatively constant as the reactant concentration changed. The best lamellar magnesium hydroxide particles in terms of size and homogeneity were 50–80 nm in length and 10 nm in thickness.

Magnesium oxide calcined from generated magnesium hydroxide was also studied for particle shape and size. Calcinating lamellar hydroxide yielded polyhedral nanoparticles of 3070 nm magnesium oxide.

Structure and Formula

Magnesium hydroxide is an inorganic base that is non-toxic. Milk of magnesia, a typical antacid, is made from its aqueous solution. Magnesium hydroxide has the chemical formula Mg(OH)2 and a molar mass of 58.32 g/mol. The centre Mg is linked to the two hydroxyl groups in the chemical structure depicted below. The compound is ionic, consisting primarily of the ions Mg2+ and OH-.

Occurrence

Magnesium hydroxide is found in nature as the mineral brucite, which is a major source of Mg(OH)2 for a variety of uses.

Derivation of the Magnesium Hydroxide Formula

The number of atoms of each element present in one molecule of a substance is represented by its chemical formula. The criss-cross method can be used to find the chemical formula for magnesium hydroxide.
If we know the valency of each constituent of a compound, we can readily express its formula using the criss-cross method. The positive part’s symbol is written on the left, while the negative part’s symbol is written on the right. Each element’s valency is written as a subscript on the side of another element’s symbol. Subscript 11 is a rare occurrence. The chemical formula of magnesium hydroxide can be calculated using this method. 

Magnesium hydroxide, on the other hand, has both magnesium (Mg2+) and hydroxyl (OH–) radicals. Magnesium has a valency of two, while the hydroxyl radical has a valency of one. The formula Mg(OH)2 is obtained by crisscrossing the valency values and utilising them as subscripts.

Magnesium Hydroxide Preparation Mg(OH)2

The following procedures are used to make magnesium hydroxide in the laboratory

  • 1. Magnesium hydroxide and hydrogen gas are formed when magnesium combines with hot water.   

Mg + H2O(hot) →Mg(OH)2

  • Magnesium hydroxide is formed when magnesium salts react with alkaline water.

Mg2 + 2OH→Mg(OH)2

  • When magnesium carbonate combines with sodium hydroxide,magnesium hydroxide is formed.

        MgCO3+2NaOH→ MgOH + Na2CO3

  • Magnesium hydroxide is formed when magnesium chloride and sodium hydroxide combine in an aqueous solution.

   MgCl2 + 2NaOH → Mg(OH)2 + 2NaCl

5. The treatment of lime [Ca(OH)2] with seawater is used to produce magnesium hydroxide on a wide scale.Magnesium hydroxide precipitates as a solid as a result.

Physical Properties of Magnesium Hydroxide Include

Magnesium Hydroxide is a solid that is white in colour. It’s an odourless substance.
2. Magnesium Hydroxide is nearly insoluble in water (low solubility).
3. Magnesium Hydroxide has a melting point of around 623K.
4.Magnesium Hydroxide has a density of 2.3446g/cm3.

Chemical Characteristics of Magnesium Hydroxide Include

  • Magnesium Hydroxide has a lower basicity. This is due to the fact that it has a low water solubility.
  • Magnesium Hydroxide decomposes into magnesium oxide and water at higher temperatures. 

Magnesium Hydroxide Has a Wide Range of Applications  as Follows

  1. Milk of Magnesia is a Magnesium Hydroxide suspension that is extensively used as an antacid. Magnesium hydroxide acts as an antacid by neutralising hydrochloric acid in the stomach and releasing water.
  2. It’s also used as a laxative (the substance used to improve bowel movements and loosen the stool).
  3. Magnesium hydroxide is a food preservative. The FDA considers it to be a safe food ingredient.
  4. Magnesium hydroxide can also be used as a deodorant.
  5. Magnesium hydroxide can be used to neutralise acidic wastewater. As a result, it is employed in the treatment of water.
  6. Brucite,a magnesium hydroxide mineral that occurs naturally, is commonly utilised as a fire retardant.

Magnesium hydroxide is utilised as a pH regulating chemical in the cosmetic sector.
It’s also used to treat heavy oil fuels and crude oil as a fuel additive.

Conclusion

Magnesium Hydroxide is a hydroxide of an alkaline earth metal. Mg(OH) in the form of ‘milk of magnesia’.It is often used as an antacid. It has no odour and is a solid white colour. It is found as brucite in nature. It can be made in the lab utilising a variety of techniques.