What is Milk of Magnesia?
Milk of magnesia, also known as magnesium dihydroxide or magnesium hydroxide, is a chemical compound with the formula Mg(OH)2. This chemical compound is known to occur naturally in the form of the mineral brucite. Under standard conditions for temperature and pressure, milk of magnesia is known to exist as a white solid that exhibits very low solubility in water. It is important to note that milk of magnesia is a vital component of antacids and certain laxatives.
Milk of magnesia is sold (often in a flavoured form) for medicinal use as chewable pills, capsules, powder, and liquid suspensions. In order to neutralise stomach acid and alleviate indigestion and heartburn, milk of magnesia is often sold as an antacid. It is also a laxative that can be used to relieve constipation. The osmotic force of magnesia, as a laxative, serves to draw fluids from the body. High doses may lead to diarrhoea and can deplete the potassium supply of the body, often resulting in muscle cramps.
Preparation of Milk of Magnesia
Milk of magnesia can be prepared by combining many solutions of magnesium salts with basic or alkaline water. The resulting chemical reactions usually involve the precipitation of solid milk of magnesia. The ionic chemical reaction that takes place here can be expressed as follows:
2OH– + Mg2+ → Mg(OH)2 [Milk of Magnesia]
However, the production of milk of magnesia on a commercial scale cannot be achieved in an efficient manner using the technique described above. For the commercial production of magnesium hydroxide, seawater can be treated with calcium hydroxide (also known as lime). It is interesting to note that one ton of milk of magnesia can be obtained from six hundred cubic metres of seawater. The reason milk of magnesia is precipitated as a solid in this reaction is because calcium hydroxide is far more soluble in water than magnesium hydroxide.
Properties of Milk of Magnesia
- The chemical formula of milk of magnesia can be represented as Mg(OH)2.
- The molar mass of this chemical compound is equal to 58.3197 grams per mole.
- Under standard conditions, this compound exists as a white solid that does not have any characteristic odour.
- The density of milk of magnesia, under standard conditions for temperature and pressure (STP), corresponds to 2.3446 grams per cubic centimetre.
- The melting point of this compound can be approximated to 350 degrees Celsius. However, it is important to note that this compound begins undergoing decomposition at this temperature gradient.
- Milk of magnesia is not very soluble in water. At a temperature of 25 degrees Celsius, the solubility of this compound in water corresponds to 0.00064 grams/100 mL. When the temperature is raised to 100 degrees Celsius, the solubility of this compound in water increases to 0.004 grams/100 mL.
- It can be noted that magnesium hydroxide crystallizes in a hexagonal crystal lattice.
Applications of Milk of Magnesia
In many life processes, magnesium is an essential element that behaves as a catalyst. In addition to the process of photosynthesis, it is also essential for the oxidation processes in the production of energy in animal cells. This element is also crucial for the development of healthy red blood cells. Without magnesium, which we receive primarily from different foods, human beings can not survive.
Magnesia milk is an alkaline (basic) suspension of water and a creamy, suspended form of Mg(OH)2 or magnesium hydroxide. It is used to neutralise excess stomach acid as an antacid. As a remedy for rashes and as a laxative, magnesium can also be used in the form of Epsom salts. In the dyeing of fabrics as well as in the tanning of leather, commercial use of Epsom salts is more essential.
Via an osmotic reaction, magnesium hydroxide has the ability to to draw water into the small intestine. Accumulation of fluid induces distension, which facilitates bowel evacuation. Prior to certain operations, magnesium is used for constipation and bowel evacuation.
Prior to surgery or surgical procedures, it is usually used to evacuate the bowl. The initiation of action is swift. In order to neutralise stomach acid, magnesium hydroxide is also used as an oral anti-acid. It is used as an antacid and mild cathartic agent in large animals. Approximately 1g / kg per single dose in cattle substantially increases the pH of the rumen and reduces the microbial activity of the rumen.
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