Ammonium Phosphate: Overview, Questions, Preparation

This chapter has multiple topics listed below:

Acids, Bases and Salts Acid Strength Difference between Acid and Bas...Examples of Bases Zinc carbonate Zinc Nitrate Aluminium Phosphate Aspartic Acid Butyric Acid Tannic acid Uses of Folic Acid Uses of Acetic Acid Lactic Acid formula Uses of Citric Acid Magnesium Nitrate Barium Iodide Dilute Acids Magnesium Phosphate Uses of Hydrochloric Acid List of Strong Acids Butanoic Acid Sodium Chlorate Barium Carbonate Chloroacetic Acid Magnesium Bicarbonate Red Cabbage Indicator Sodium Hexametaphosphate Zinc Hydroxide Potassium Iodate Peroxydisulfuric Acid Ph of Acids and Bases Potassium Bromate Weak Acid Examples Weak Bases Magnesium Hydroxide Monosodium Glutamate Potassium Hydroxide Nitrous Acid Henderson Hasselbalch Equation Difference between Alkali and B...Properties of Bases Sodium Citrate Ammonium Phosphate Chemical Indicators Chromic Acid Perchloric Acid Uses of Sodium Hydroxide Zinc Acetate

Yamini Saini

Updated on Jun 30, 2021 06:48 IST

Ammonium phosphate is a volatile compound with the chemical formula (NH4)3PO4, composed of ammonium and phosphate salt.

What is Ammonium Phosphate?

Ammonium phosphate is processed in a molten state by blending ammonium phosphate and urea. Significant heat is produced that transforms the sulphate of ammonium phosphate into a molten state. It comprises a group of mono-ammonium phosphate and diammonium phosphate nitrogen phosphorus products, mixtures of the two, or a combination of ammonium nitrate or ammonium sulphate.

Table of Contents

Properties of Ammonium Phosphate
Uses of Ammonium Phosphate
Illustrated Examples
FAQs on Ammonium Phosphate

Properties of Ammonium Phosphate

Density	1.619 g/cubic cm
Molecular weight/Molar mass	149.09 g/mol
Boiling point	130°C
Melting point	155 °C (311 °F; 428 K)
Chemical formula	H9N2O4P

Physical Properties of Ammonium Phosphate

Odour	Ammonia odour
Appearance	White, tetrahedral crystals
Complexity	46.5
Covalently-Bonded Unit	3
Hydrogen Bond Donor	3
Solubility	Readily soluble in water
Solubility pH	4 to 4.5

Chemical Properties of Ammonium Phosphate

Ammonium phosphate quickly undergoes a decomposition reaction with very toxic gases released. Phosphoric acid and ammonia are formed.

(NH4)3PO4 → 3NH3 + H3PO4

Ammonium phosphate reacts by forming lead phosphate and ammonium nitrate with lead nitrate.

4(NH4)3PO4 + 3Pb(NO3)4 → Pb3(PO4)4 + 12NH4NO3

Uses of Ammonium Phosphate

A broad common term for several fertiliser products containing both nitrogen and phosphate is ammonium phosphate.
As a source of usable P2O5,ammonium phosphates are becoming increasingly essential. In ammonium phosphates, P2O5,is much weaker than in triple superphosphate.
Used mainly as a solid fertiliser, but can also be used in solutions.
Used as intumescent paint and mastic components where they act as a catalyst for acid.
Used in paints that contain the carbonic portion of pentaerythritol and the unique compound of melamine.

Ammonium Phosphate in Class 10

This concept is taught under the chapter ‘Acids, Bases and Salts.’ You will be taught about the structure of ammonium phosphate, its reactions and characteristic equations. The weightage is 5 marks.

Illustrated Examples

Is ammonium phosphate a weak electrolyte?

No. Ammonium phosphate (NH4)3PO4 is a very strong electrolyte.

What is the ammonium phosphite formula?

(NH4)3PO4

Why does NH3 act as a Lewis base?

Nitrogen atoms in NH3 have one lone pair of electrons which is available for donation. Therefore, it acts as a Lewis base.

FAQs on Ammonium Phosphate

Q. For what reason is ammonium phosphate used?

A. A high source of elemental nitrogen used as an ingredient in some fertilisers is ammonium phosphate. This is often applied as a flame retardant in thermoplastic formulations.

Q. Why is ammonium phosphate used as a fertiliser?

A. Ammonium phosphate provides the lawns with nitrogen and phosphates that lack nutrients. Ammonium phosphate is a fast-release fertiliser that can be used for new grass planting, watering, tracking, or lawn renovation.

Q. What is the difference between ammonia and ammonium?

A. Ammonia comprises one nitrogen and three hydrogens, similar to one nitrogen and four ammonium-formed hydrogens. A low, unionised base is ammonia. It is ionised into ammonium on the other hand. A major difference between the two is that, while ammonium does not smell, ammonia gives off a strong odour.

Q. Is the ammonium phosphate an acid?

A. Ammonium phosphate is an ammonium salt consisting of orthophosphoric acid. Formula (NH4)3PO4 is an extremely unstable compound. It is enigmatic and, due to its uncertainty, of little economic interest.

Q. Why is ammonium phosphate water-soluble?

A. It is water-soluble and lacks ammonia, and as an aqueous solution on the boil, the acid phosphate (NH4)(H2PO4) is formed. Ammonium phosphate is a good source of elemental nitrogen and is used as an ingredient in some fertilisers. This is often applied as a flame retardant in thermoplastic formulations.