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Magnesium Phosphate

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The Chemical Formula of Magnesium Phosphate

Magnesium phosphate is an ionic compound composed of the magnesium cation (Mg2+) and phosphate anion (PO43-). This is a salt with a hydrated crystalline structure. Being hydrated, the water of crystallization is found in the crystal structure of magnesium phosphate. It is found in amorphous forms also. The chemical formula of magnesium phosphate is Mg3(PO4)and magnesium phosphate chemical formula has the molecular weight of 262.855 g/mol. This salt is found in nature as hydrated monomagnesium phosphate, dimagnesium phosphate or trimagnesium phosphate.  It appears as a white crystalline powder. It has a density of 2.195 g/mL at 298K. It has a melting point of 1457K.

 

Structure of Magnesium phosphate

In the most common magnesium phosphate, three divalent magnesium cations and two phosphate anions are attracted by means of the electrostatic force of attraction and an electrovalent structure of magnesium phosphate is produced. Molecules of water of crystallization may be attached to their crystals also. 

 

Different Types of Magnesium Phosphate

Besides the most common form dimagnesium phosphate(Mg3(PO4)2.xH2O) different types of hydrated structures like monomagnesium phosphate, dimagnesium phosphate are found. Their chemical formulae are Mg(H2PO4)2.xH2O, MgHPO4.xH2O respectively. 

 

Preparation of Magnesium Phosphate

Trimagnesium phosphate can be prepared in the laboratory by neutralizing tribasic orthophosphoric acid with magnesium hydroxide. The chemical equation is-

2H3PO4 + 3Mg(OH)2 = Mg3(PO4)2 + 6H2O

 

Monomagnesium phosphate tetrahydrate occurs in equilibrium with dimagnesium phosphate trihydrate. Dimagnesium phosphate trihydrate can be prepared by the action of aqueous solution of any magnesium salt on any diacidic base or diammonium orthophosphate solution.

 

Chemical Nature of Magnesium Phosphate

Magnesium phosphate is a hydrated crystalline white powder with no odor. X-ray diffraction studies are utilized to detect the nature of chemical bond formation. 

 

Action of water

It is a water-soluble salt, which on the addition of water produces magnesium hydroxide and orthophosphoric acid which is just the reverse reaction of its formation.

Mg3(PO4)2 + 6H2O = 2H3PO4 + 3Mg(OH)2

 

Action of Hydrochloric Acid

Magnesium phosphate reacts with hydrochloric acid to produce magnesium chloride salt and orthophosphoric acid.

Mg3(PO4)2+ HCl = MgCl2 + H3PO4

 

Calcium Magnesium Phosphate

Calcium magnesium phosphate or calcium magnesium orthophosphate has the molecular formula of CaMgO4P+. It is a special class of magnesium phosphate where calcium ions are also included. 

 

Uses of Magnesium Phosphate

Magnesium phosphate is a good source of both magnesium and phosphate. It is mostly used as a food stabilizer in the formulation of infant processed foods in order to fulfill proper nutrients and used as supplements. 

 

Importance of Magnesium Phosphate for Human Health

Magnesium is an important macronutrient of the body. Magnesium phosphate is an essential substance in the formation of bones and muscles. It is very important for relaxation of the muscle. In order to avoid muscle cramping, it must be used. It supports the membrane, maintains normal muscle activity including heart, helps in the metabolism of carbohydrate, protein, and fat, helps in the manufacture of protein, regulates nerve cells. Besides, it is important in the formation of teeth. 

 

Proper Dosage of Intaking Magnesium Phosphate

Less than 350 mg daily is the safe dosage for intaking magnesium phosphate in healthy adults, otherwise, it would be fatal to intake an m much higher dosage as there are lots of side effects.

 

Side Effects 

Regular and long term usage of a high dosage of magnesium phosphate can cause an imbalance of magnesium and phosphate in the body. As a result, it can cause nausea, vomiting, stomach upset, headache, constipation, diarrhea, tiredness, mental confusion or other problems. It can decrease blood pressure too. The most fatal part of these side effects may be an irregular heartbeat, breathing problems, coma, and ultimately, death. So, it is very important to continue its medicinal use as a proper dosage.

 

Food Sources of Magnesium and Phosphate

Many food sources are very much rich in magnesium and phosphate. Dark chocolate, avocado, nuts, legumes, tofu, flax, pumpkin, fatty fishes like salmon, mackerel, banana, spinach, mustard are the rich sources of magnesium. Besides, chicken, pork, seafood like cuttlefish, crab, salmon, catfish, dairy products, pumpkin, sunflower oil, nuts are important sources of phosphorus. 

 

Signs of Deficiency

Magnesium deficiency is caused by a low magnesium diet for an extended period, malabsorption, and substantial losses from alcohol consumption or the use of drugs that deplete magnesium. The signs of deficiency include:

  • Fatigue, weakness

  • Poor appetite

  • Nausea, vomiting

  • Numbness or tingling in the skin

  • Muscle cramps

  • Seizures

  • Abnormal heart rate

 

Signs of Toxicity

Toxicity from food is uncommon since the kidneys eliminate excess magnesium in the urine. Long-term usage of high-dosage supplements, on the other hand, may result in hazardous amounts. People with kidney disease have a higher risk of poisoning because their kidneys aren't operating correctly and can't filter out excess magnesium. Signs of toxicity are:

  • Nausea, vomiting

  • Diarrhea

  • Low mood, depression

  • Muscle weakness

  • Low blood pressure, abnormal heartbeat

  • Heart attack 


Risk Factors of Deficiency

Alcohol Abuse - Long-term excessive alcohol consumption is linked to a low-magnesium diet, a digestive disturbance that leads to malabsorption, and issues with multiple organs that can cause too much magnesium to be flushed out through urine.


Older Age - According to national dietary studies, the elderly consume less magnesium. Magnesium absorption in the stomach decreases with age, whereas excretion in the urine increases. Furthermore, older persons are more likely to be on chronic illness drugs that reduce magnesium stocks.


Conditions with malabsorption - The quantity of magnesium absorbed can be reduced by diseases that interfere with digestion. The ileum, the biggest portion of the small intestine, absorbs the majority of magnesium, which can be affected in disorders like celiac and Crohn's disease. The ileum is occasionally removed after surgery for colon cancer, ulcerative colitis, or Crohn's disease, which increases the risk of insufficiency.


Type 2 diabetes - Insulin resistance or uncontrolled diabetes can lead the kidneys to produce more urine to flush out excess blood sugar levels. Magnesium may be flushed out as a result of the increased volume of urine.


Did You Know

  • Only one cup of chicken contains 330 grams of phosphorus. 

  • Dark chocolates are rich in magnesium so eating chocolates is sometimes good for health.

  • Previously, it was thought that magnesium and calcium were the same elements.

  • When magnesium wire is burnt in the presence of air or oxygen, magnesium oxide is produced producing white light. This property is used in fireworks, flares, photographic flashbulbs, and pyrotechnics.

  • Magnesium phosphate is used to prevent vitamin E deficiency. 

  • Magnesium phosphate maintains the balance of other minerals of the body and helps to regulate hormonal functions.

  • Magnesium phosphate is used as food supplements as magnesium phosphate powder or capsules that need to be consumed daily.

  • The metal, magnesium makes up only 2 per cent of the earth’s crust.

  • The name, magnesium comes from the name of a district of Greece, Magnesia, where the mineral of the magnesium, Magnesia alba was first found.

FAQs on Magnesium Phosphate

1. What exactly is Magnesium Phosphate in simple terms?

Magnesium Phosphate is an ionic compound, which means it's a type of salt. It is formed from magnesium, a metal, and phosphate, a polyatomic ion. You'll commonly find it as a white, crystalline powder that doesn't dissolve well in water.

2. How do you figure out the chemical formula for Magnesium Phosphate, Mg₃(PO₄)₂?

To find the formula, you need to balance the charges of the ions. Magnesium forms a cation with a +2 charge (Mg²⁺), and the phosphate ion has a -3 charge (PO₄³⁻). To make the compound neutral, you need three magnesium ions (3 x +2 = +6) and two phosphate ions (2 x -3 = -6). This balancing act gives us the final formula: Mg₃(PO₄)₂.

3. What are the most common uses of Magnesium Phosphate in daily life and industry?

Magnesium Phosphate has several important applications. Its main uses include:

  • Food Additive: It's used as an acidity regulator and nutrient supplement in some foods.
  • Dietary Supplements: It serves as a source of both magnesium and phosphorus, which are important for bone and muscle health.
  • Fertilizers: It provides essential nutrients to plants, supporting healthy growth.
  • Animal Feed: It is added to animal feed to ensure livestock get adequate minerals.

4. What are the key physical and chemical properties of Magnesium Phosphate?

The main properties of Magnesium Phosphate are: It is a white, odourless crystalline solid at room temperature. It has a very high melting point. Chemically, it is best known for being sparingly soluble in water but will dissolve in acidic solutions. It is a stable, non-reactive salt under normal conditions.

5. How is Magnesium Phosphate different from Magnesium Sulfate (Epsom salt)?

While both are magnesium salts, their key difference lies in the anion they are paired with and their solubility. Magnesium Phosphate contains the phosphate ion (PO₄³⁻) and is poorly soluble in water. Magnesium Sulfate, on the other hand, contains the sulfate ion (SO₄²⁻) and is highly soluble in water, which is why it's commonly used in baths as Epsom salt.

6. Why is Magnesium Phosphate considered an important compound in biology?

Its importance comes from its two components. Magnesium is vital for muscle function, nerve transmission, and hundreds of enzymatic reactions. The phosphate group is a fundamental building block of DNA, RNA, and ATP, the main energy currency of our cells. Together, they play a crucial role in maintaining bone structure and overall metabolic health.

7. Why doesn't Magnesium Phosphate dissolve well in water?

Magnesium Phosphate is considered insoluble or sparingly soluble in water because of the strong attraction between its ions. The ionic bonds between the Mg²⁺ and PO₄³⁻ ions are very strong, creating a stable crystal lattice. Water molecules do not have enough energy to easily break apart this strong lattice, which is why very little of the salt dissolves.

8. How is Magnesium Phosphate typically prepared in a laboratory setting?

A common method to prepare Magnesium Phosphate is through a precipitation reaction. This involves mixing a solution of a soluble magnesium salt (like magnesium chloride, MgCl₂) with a solution of a soluble phosphate salt (like sodium phosphate, Na₃PO₄). The insoluble Magnesium Phosphate then forms as a solid precipitate, which can be filtered, washed, and dried.