Sodium Phosphate (Na3PO4) - Structure, Molecular Mass, FAQs

Q: What is sodium phosphate and write sodium phosphate formula.

Sodium phosphate is a salt formed when sodium (Na + ) and phosphate (PO 4 3− ) ions combine. Sodium phosphate and its salt may exist in hydrated or anhydrous form. Commonly known as phospho soda, is saline purgative (purgative is a medicine for better digestion). Sodium phosphate or its other forms are produced when hydrogen atom(s) in phosphoric acid (H 3 PO 4 ) are replaced by sodium atoms. Removal of one hydrogen atom forms monobasic form of sodium phosphate, removal of two hydrogen atoms forms dibasic form of sodium phosphate and removal of all hydrogen atoms forms tribasic form of sodium phosphate. Being a salt, sodium phosphate and its other forms are crystalline solids or white powders. They are colorless to white in appearance. Sodium phosphate chemical formula is Na 3 PO 4 .

Q: Write name of Na2HPO4 and Na3PO4.

Na 2 HPO4 name is Disodium phosphate and Na 3 PO 4 compound name is trisodium phosphate.

Q: Is Na3PO4 acid or base?

Na 2 PO 4 , trisodium phosphate is slightly acidic in nature based on its pKa value.

Q: Na3PO4 is which type of salt?

Na 3 PO 4 is phosphate salt of sodium.

Q: Is Na2HPO4 acid or base?

Na 2 HPO 4 , monosodium phosphate is neutral that is neither acid nor base.

Q: Write sodium phosphide formula.

Sodium phosphide formula is Na 3 P.

Sodium Phosphate (Na3PO4) - Structure, Molecular Mass, FAQs

Edited By Team Careers360 | Updated on Jul 12, 2022 03:38 PM IST

What is sodium phosphate?

Sodium phosphate is a salt formed when sodium (Na⁺) and phosphate (PO₄³⁻) ions combine. Sodium phosphate formula is Na₃PO₄. Sodium phosphate and its salt may exist in hydrated or anhydrous form. Commonly known as phospho soda, is saline purgative (purgative is a medicine for better digestion). Sodium phosphate or its other forms are produced when hydrogen atom(s) in phosphoric acid (H₃PO₄) are replaced by sodium atoms. Removal of one hydrogen atom forms monobasic form of sodium phosphate, removal of two hydrogen atoms forms dibasic form of sodium phosphate and removal of all hydrogen atoms forms tribasic form of sodium phosphate. Being a salt, sodium phosphate and its other forms are crystalline solids or white powders. They are colorless to white in appearance.

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What is sodium phosphate?
Family of sodium phosphate
Sodium phosphate uses
Effects of sodium phosphate

Na3PO4 structure

Figure 1 Na₃PO₄ structure.

Sodium phosphate is also known as sodium orthophosphate, tribasic sodium phosphate, trisodium phosphate. Density of trisodium phosphate is 1.62 g/cm³. Sodium phosphate molecular weight (or molar mass of sodium phosphate) is 163.94 g/mol.

Boiling point of sodium phosphate is 100 °C and the melting point of sodium phosphate is 1,583 °C. The value of trisodium phosphate solubility is ‘soluble in water’.

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Family of sodium phosphate

Monophosphates

Sodium monophosphate salts are mostly derived from orthophosphate (PO₄³⁻), dihydrogen phosphate (H2PO₄⁻) and hydrogen phosphate (HPO₄²⁻).

Some name and the formula of different sodium phosphate is given below.

monosodium phosphate (anhydrous) NaH₂PO₄ ,disodium phosphate (anhydrous)Na₂HPO₄, disodium phosphate (dihydrate) HNa₂PO₄(H₂O)₂, disodium phosphate (heptahydrate)HNa₂PO₄(H₂O)₇, monosodium phosphate (monohydrate) NaH₂PO₄(H₂O), monosodium phosphate (dihydrate) NaH₂PO₄(H₂O)₂, disodium phosphate (octahydrate) HNa₂PO₄(H₂O)₈, disodium phosphate (dodecahydrate) HNa₂PO₄(H₂O)₁₂,

Diphosphates and polyphosphates

A number of important salts are produced when sodium reacts with pyrophosphates; also known as Diphosphates, triphosphates and high polymers.

Some name and formula are given below.

monosodium diphosphate (anhydrous) NaH₃P₂O₇, disodium diphosphate (hexahydrate) Na₂H₂P₂O₇(H₂O)₆, trisodium diphosphate (anhydrous) Na₃HP₂O₇, trisodium diphosphate (monohydrate) Na₃HP₂O₇(H₂O), disodium diphosphate (anhydrous) Na₂H₂P₂O₇, trisodium diphosphate (nonahydrate) Na₃HP₂O₇(H₂O)₉, tetrasodium diphosphate (decahydrate) Na₄P₂O₇(H₂O)₁₀

Triphosphate salts of sodium like tetraphosphates and sodium triphosphate are also known. Metaphosphates, a name given to cyclic phosphates such as Na₃P₃O₉ trimer sodium trimetaphosphate and tetramer Na₄P₄O₁₂ also exist.

When NaH₂PO₄ and Na₂HPO₄ are heated, polymeric sodium phosphates are formed. To form a specific polyphosphate annealing and heating process is altered. Some of such specific polyphosphate is Graham’s salt, Kurrol’s salt and Maddrell’s salt. Graham salt has a formula NaO(NaPO₃)Na₂. Kurrol’s salt and Maddrell’s salt has a general formula [NaPO₃]n[NaPO₃(OH)]₂ where n can have a value upto 2000. . Kurrol’s salt and Maddrell’s salt are crystalline polyphosphates with a high molecular weight.

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Sodium phosphate uses

Sodium phosphate and its other forms are very commonly used in a lot of everyday products. This is because sodium phosphate is inexpensive and is nontoxic when taken in adequate amounts. Some sodium phosphate uses includes:

Sodium phosphate is used in food and water treatment.
Sodium phosphate is used as an emulsifier in processed cheese production.
Sodium phosphate is used as a thickening agent in soups, etc.
Sodium phosphate is used as a leavening agent for baked food.
Sodium phosphate is used to control pH of processed food.
Sodium phosphate is used as medicine for constipation.
Sodium phosphate is used as pharmaceuticals to prepare the bowel for further medical processes.
Sodium phosphate is used in detergents for the purpose of softening hard water
Sodium phosphate is used in anti-rust solutions as an efficient solution.
Sodium phosphate is used in fertilizers
Sodium phosphate is used in animal food as preservative
Sodium phosphate is used in soaps.
Sodium phosphate is used as a food additive.
Sodium phosphate particularly disodium pyrophosphate is often used as a buffer.
Sodium phosphate is used in toothpaste to remove magnesium from saliva which prevents cavities and plaques.

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Effects of sodium phosphate

As discussed, sodium phosphate is used in bowel preparation for medical procedures like colonoscopy. High levels of sodium phosphate intake carries a hazardous risk of kidney failure. Sodium phosphates also play a major role in eutrophication of water. Eutrophication involves increased algal growth known as algal bloom due to presence of excess phosphate which in turn causes decreased oxygen levels in water. Sodium phosphates generally reach water bodies like ponds, rivers or lakes by washing off detergents, soaps, factories or fertilizers.

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Frequently Asked Questions (FAQs)

1. What is sodium phosphate and write sodium phosphate formula.

Sodium phosphate is a salt formed when sodium (Na⁺) and phosphate (PO₄³⁻) ions combine. Sodium phosphate and its salt may exist in hydrated or anhydrous form. Commonly known as phospho soda, is saline purgative (purgative is a medicine for better digestion). Sodium phosphate or its other forms are produced when hydrogen atom(s) in phosphoric acid (H₃PO₄) are replaced by sodium atoms. Removal of one hydrogen atom forms monobasic form of sodium phosphate, removal of two hydrogen atoms forms dibasic form of sodium phosphate and removal of all hydrogen atoms forms tribasic form of sodium phosphate. Being a salt, sodium phosphate and its other forms are crystalline solids or white powders. They are colorless to white in appearance. Sodium phosphate chemical formula is Na₃PO₄.

2. Write name of Na2HPO4 and Na3PO4.

Na₂HPO4 name is Disodium phosphate and Na₃PO₄ compound name is trisodium phosphate.

3. Is Na3PO4 acid or base?

Na₂PO₄, trisodium phosphate is slightly acidic in nature based on its pKa value.

4. Write Na3PO4 molar mass.

Sodium phosphate molecular weight (or molar mass of sodium phosphate) is 163.94 g/mol.

5. Na3PO4 is which type of salt?

Na₃PO₄ is phosphate salt of sodium.

6. Is Na2HPO4 acid or base?

Na₂HPO₄, monosodium phosphate is neutral that is neither acid nor base.

7. Write sodium phosphide formula.

Sodium phosphide formula is Na₃P.

8. Write PO4 molar mass.

Molecular weight of phosphate is 94.971361 g/mol. It can be calculated by adding molecular weight of phosphorus (molecular weight of one P atom is 30.973761 g/mol) and molecular weight of four oxygen atoms (molar mass of one oxygen is 15.9994 g/mol).

9. Write sodium phosphate enema bp uses.

Sodium phosphate enema bp uses are: