:Sodium pyrosulfate

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| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 407956312

| Reference = {{cite book |editor-last=Olsen |editor-first=J. C. |title=Van Nostrand's Chemical Annual |publisher=Chapman and Hall |location=London |year=1934 }}

| ImageFile = Sodium pyrosulfate.png

| ImageSize = 150px

| IUPACName = Disodium disulfate

| OtherNames = Sodium pyrosulphate; Disulfuric acid disodium salt, disodium disulfate; Sodium metabisulfate

| Section1 = {{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|??}}

| CASNo = 13870-29-6

| ChemSpiderID = 7970254

| EC_number = 237-625-5

| PubChem = 9794487

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 111016

| SMILES = [Na+].[Na+].[O-]S(=O)(=O)OS(=O)(=O)[O-]

| StdInChI=1S/2Na.H2O7S2/c;;1-8(2,3)7-9(4,5)6/h;;(H,1,2,3)(H,4,5,6)/q2*+1;/p-2

| StdInChIKey = JXAZAUKOWVKTLO-UHFFFAOYSA-L

}}

| Section2 = {{Chembox Properties

| Formula = Na₂S₂O₇

| MolarMass = 222.12 g/mol

| Appearance = Translucent white crystals

| Density = 2.658 g/cm³

| MeltingPtC = 400.9

| BoilingPt= decomposes at

| BoilingPtC = 460

| Solubility = hydrolyses{{cite journal|author1=Heinz K. Hofmeister|author2=John R. Van Wazer|title=Hydrolysis of Sodium Pyrosulfate |journal=Inorganic Chemistry|volume=1|issue=4|pages=811–812|publisher=ACS|year=1962|doi=10.1021/ic50004a019}}

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| Section3 = {{Chembox Hazards

| MainHazards =

| FlashPt =

| AutoignitionPt =

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Sodium pyrosulfate is an inorganic compound with the chemical formula of Na₂S₂O₇. It is a colorless salt.{{cite journal|author=Helmold Plessen|title=Sodium Sulfates|journal=Ullmann's Encyclopedia of Industrial Chemistry|publisher=Wiley-VCH|year=2000|location=Weinheim|doi=10.1002/14356007.a24_355|isbn=978-3527306732}} It hydrolyses in water to form sodium bisulfate with a chemical formula of NaHSO4 which has a pH of around 1.