ammonium phosphate

{{Chembox

| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 428203184

| ImageFile = Ammonium phosphate.png

| ImageFile1 = Triammonium-phosphate-3D-balls.png

| ImageSize1 = 240px

| ImageName1 = Ball-and-stick model of three ammonium cations and one phosphate anion

| Reference =

{{cite book | last = Lide | first = David R. | year = 1998

| title = Handbook of Chemistry and Physics

| edition = 87 | volume =

| location = Boca Raton, Florida

| publisher = CRC Press

| isbn = 978-0-8493-0594-8 | pages = 4–42, 5–19}}

| IUPACName = ammonium phosphate

| OtherNames = triammonium phosphate

|Section1={{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 140090

| InChI = 1/3H3N.H3O4P/c;;;1-5(2,3)4/h3*1H3;(H3,1,2,3,4)

| InChIKey = ZRIUUUJAJJNDSS-UHFFFAOYAA

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/3H3N.H3O4P/c;;;1-5(2,3)4/h3*1H3;(H3,1,2,3,4)

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = ZRIUUUJAJJNDSS-UHFFFAOYSA-N

| CASNo_Comment = {{cascite|correct|CAS}}

| CASNo = 10361-65-6

| EC_number = 269-789-9

| UNII_Ref = {{fdacite|changed|FDA}}

| UNII = 2ZJF06M0I9

| PubChem = 159282

| SMILES = [O-]P([O-])([O-])=O.[NH4+].[NH4+].[NH4+]

}}

|Section2={{Chembox Properties

| Formula = (NH₄)₃PO₄

| Appearance = White, tetrahedral crystals

| Density =

| MeltingPt =

| BoilingPt =

| Solubility = 58.0 g/100 mL (25 °C)

| SolubleOther = Insoluble in acetone{{cite book |author1=John Rumble |title=CRC Handbook of Chemistry and Physics |date=June 18, 2018 |publisher=CRC Press |isbn=978-1138561632 |pages=4–41|edition=99th |language=English}}

| MolarMass=149.09 g/mol}}

|Section3={{Chembox Hazards

| GHSPictograms = {{GHS07}}

| GHSSignalWord = Warning

| HPhrases = {{H-phrases|302|319}}

| PPhrases = {{P-phrases|264|270|280|301+312|305+351+338|330|337+313|501}}

| NFPA-H = 2

| NFPA-F = 0

| NFPA-R = 0

| MainHazards =

| FlashPt =

| AutoignitionPt = }}

|Section4={{Chembox Thermochemistry

| DeltaHf = −1671.9 kJ/mol

| DeltaHc =

| Entropy =

| HeatCapacity = }}

|Section8={{Chembox Related

| OtherCations = Trisodium phosphate
Tripotassium phosphate

| OtherCompounds = Diammonium phosphate
Monoammonium phosphate

}}

}}

Ammonium phosphate is the inorganic compound with the formula (NH₄)₃PO₄. It is the ammonium salt of orthophosphoric acid. A related "double salt", (NH₄)₃PO₄^.(NH₄)₂HPO₄ is also recognized but is impractical to use. Both triammonium salts evolve ammonia. In contrast to the unstable nature of the triammonium salts, the diammonium phosphate (NH₄)₂HPO₄ and monoammonium salt (NH₄)H₂PO₄ are stable materials that are commonly used as fertilizers to provide plants with fixed nitrogen and phosphorus.{{Ullmann|first1=Klaus|last1=Schrödter|first2=Gerhard|last2=Bettermann|first3=Thomas |last3=Staffel|first4=Friedrich|last4=Wahl|first5=Thomas|last5=Klein||first6=Thomas|last6=Hofmann|title=Phosphoric Acid and Phosphates|year=2008|doi=10.1002/14356007.a19_465.pub3}}

Ammonium phosphate is the main ingredient in pink fire retardant. {{Cite web |last=Press • • |first=Tammy Webber {{!}} The Associated |date=2025-01-14 |title=What to know about the pink flame retardants are being used for California fires |url=https://www.nbclosangeles.com/news/local/pink-flame-retardants-california-wildfires/3604543/ |access-date=2025-01-15 |website=NBC Los Angeles |language=en-US}}