Phosphate (PO₄³⁻)

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Introduction to Phosphate (PO₄³⁻)

Phosphate is derived from Orthophosphoric acid(H3PO4), oxoacid of phosphorus, belonging to group 15 of P-Block in the periodic table. After removing three H atoms from orthophosphoric acid, we get phosphate ions. Pyrophosphates are condensed forms of phosphate. In nature, Phosphorus is present in phosphate ions in rocks, so it is a mineral, formed by the sedimentation process of thousands of years. It is of great importance and used widely as fertilizers, which are required for enhancing crop yield, soil quality, and meeting the needs of nutrients required to soil and crops. By converting into other forms of phosphorus, it is used widely in different industries.

Structure of Phosphate

As we already mentioned, phosphate is formed by removing three H atoms from orthophosphoric acid, so it acquires a negative charge and is known as a conjugate ion or anion. The molecular mass of phosphate is 94.97gm per mol. It has a central P atom surrounded by 4 O atoms in tetrahedral fashion while having an overall negative charge of -3.

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As we can see, H atoms are now removed from the phosphate, so it is less soluble in water at STP. When 1 H atom is removed from H3PO3, it results in the formation of dihydrogen Phosphate ion [H2PO4]- and subsequent removal of other hydrogens gives hydrogen phosphate [HPO4]2-. So, different ions like diammonium phosphate, sodium phosphate, are formed and their salts are used for various purposes.

Properties of Phosphate

  1. It is present in solid form, in rocks, teeth, and bones, in soil.

  2. It has a boiling point of 553K and the melting point is 373.1K.

  3. Phosphate is required for the human body, 800mg/day is a basic requirement. Excess intake of phosphate is harmful leading to serious kidney problems and osteoporosis.

  4. It is less soluble in water. If we keep on changing the cation part, solubility varies accordingly. If we try to compensate for the negative charge by attaching other groups, solubility decreases further.

Importance of Phosphate

  •  As we know Phosphate is present in our bones, teeth; it is clearly visible that it is required for normal body functioning. Regular intake of it from various food sources is necessary. Lack and excess of which may lead to severe health issues. It is present in cheese, sausages, milk products, whole grains, meat, fish, beans, etc.

  • Phosphate is obtained from rocks and it is widely used as fertilizers.

  • Phosphate is used to convert it into other forms of phosphorus which are used by various industries like makeup and animal food industries.

  • In tubes of toothpaste, it is used frequently as octacalcium phosphate for providing free flow to the paste.

  • It is commonly used in fire extinguishers.

  • It is used by various pharmaceutical companies for producing medicines for health issues related to bones and teeth.

  • Calcium phosphate is now gaining special interest in agriculture due to its properties as a nano growth promoter.

  • Single super phosphate (SSP) was the first commercial mineral fertilizer which led to the development of the modern plant nutrient industry.

FAQ (Frequently Asked Questions)

1. What is phosphate used for?

As we know, Phosphate is obtained from rocks, it is processed to form other forms of phosphorus which are used by agricultural industries as fertilizers, pharmaceutical industries as drugs, cosmetic industries as part of various products, and food industries as a source of phosphorus in the body

2. What food contains Phosphates?

It is found in protein-rich meals like meat, eggs, fish, milk, dairy products, whole grains, green vegetables.Non-vegetarian meals provide higher amounts of phosphate as compared to plant-based diet.

3. What are the symptoms of phosphate deficiency?

In the human body, Phosphate is mainly present in bones and teeth. So, it is understandable that deficiency of it will affect the bones and teeth. The main symptoms are decreased growth in children, poor teeth and bone development, weak bones, appetite loss, weakness, numbness in body parts.