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	{{chembox		{{chembox
			| Verifiedfields = changed
⚫	| verifiedrevid = 409852369
			| Watchedfields = changed
		⚫	| verifiedrevid = 446461906
	| Name = Sodium chromate		| Name = Sodium chromate
	| ImageFile = Sodium-chromate.svg		| ImageFile = Sodium-chromate.svg
	<!-- | ImageSize = 250px -->
	| ImageName =		| ImageName =
	| ImageFile1 = Chroman sodný.JPG		| ImageFile1 = Chroman sodný.JPG
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	| IUPACName = Sodium chromate		| IUPACName = Sodium chromate
	| OtherNames = Chromic acid, (Na<sub>2</sub>CrO<sub>4</sub>), disodium salt<br/>Chromium disodium oxide<br/>Rachromate		| OtherNames = Chromic acid, (Na<sub>2</sub>CrO<sub>4</sub>), disodium salt<br/>Chromium disodium oxide<br/>Rachromate
	| Section1 = {{Chembox Identifiers		|Section1={{Chembox Identifiers
	| CASNo = 7775-11-3		| CASNo = 7775-11-3
	| CASNo_Ref = {{cascite}}		| CASNo_Ref = {{cascite|correct|CAS}}
			| ChemSpiderID = 22896
			| UNII_Ref = {{fdacite|correct|FDA}}
			| UNII = 6A49BO6K4M
	| PubChem = 24488		| PubChem = 24488
			| ChEBI_Ref = {{ebicite|correct|EBI}}
			| ChEBI = 78671
	| EINECS = 231-889-5		| EINECS = 231-889-5
	| RTECS = GB2955000		| RTECS = GB2955000
	| UNNumber = 3288		| UNNumber = 3288
			| InChI = 1S/Cr.2Na.4O/q;2*+1;;;2*-1
			| SMILES = (=O)(=O)..
	}}		}}
	| Section2 = {{Chembox Properties		|Section2={{Chembox Properties
	| Formula = Na<sub>2</sub>CrO<sub>4</sub>		| Formula = Na<sub>2</sub>CrO<sub>4</sub>
	| MolarMass = 161.97 g/mol		| MolarMass = 161.97 g/mol
	| Density = 2.698 g/cm<sup>3</sup>		| Density = 2.698 g/cm<sup>3</sup>
	| MeltingPt = 762 °C		| MeltingPtC = 792
	| Solubility = 53 g/100 ml (20 °C)		| MeltingPt_notes = (anhydrous) <br> 20 °C (decahydrate)
			| Solubility = 31.8 g/100 mL (0 °C) <br> 84.5 g/100 mL (25 °C) <br> 126.7 g/100 mL (100 °C)
			| Solvent1 = methanol
			| Solubility1 = 0.344 g/100 mL (25 °C)
			| SolubleOther = slightly soluble in ]
	| Appearance = yellow crystals		| Appearance = yellow crystals
			| Odor = odorless
			| MagSus = +55.0·10<sup>−6</sup> cm<sup>3</sup>/mol
	}}		}}
	| Section3 = {{Chembox Structure		|Section3={{Chembox Structure
	| CrystalStruct = orthorhombic (hexagonal above 413 °C)		| CrystalStruct = orthorhombic (hexagonal above 413 °C)
	}}		}}
	| Section4 = {{Chembox Thermochemistry		|Section4={{Chembox Thermochemistry
	| DeltaHf = −1329 kJ/mol		| DeltaHf = −1329 kJ/mol
			| DeltaGf = -1232 kJ/mol
			| Entropy = 174.5 J/mol K
			| HeatCapacity = 142.1 J/mol K
	}}		}}
	| Section7 = {{Chembox Hazards		|Section7={{Chembox Hazards
	| ExternalMSDS =		| ExternalSDS =
			| GHSPictograms = {{GHS05}}{{GHS06}}{{GHS07}}{{GHS08}}{{GHS09}}
	| EUIndex = 024-018-00-3
			| GHSSignalWord = Danger
	| EUClass = ]<br/>]<br/>Repr. Cat. 2<br/>Very toxic ('''T+''')<br/>Harmful ('''Xn''')<br/>Corrosive ('''C''')<br/>Dangerous for the environment ('''N''')
			| HPhrases = {{H-phrases|301|312|314|317|330|334|340|350|360|372|410}}
	| RPhrases = {{R45}}, {{R46}}, {{R60}}, {{R61}}, {{R21}}, {{R25}}, {{R26}}, {{R34}}, {{R42/43}}, {{R48/23}}, {{R50/53}}
			| PPhrases = {{P-phrases|201|202|260|261|264|270|271|272|273|280|281|284|285|301+310|301+330+331|302+352|303+361+353|304+340|304+341|305+351+338|308+313|310|312|314|320|321|322|330|333+313|342+311|363|391|403+233|405|501}}
	| SPhrases = {{S53}}, {{S45}}, {{S60}}, {{S61}}
	| NFPA-H = 3		| NFPA-H = 3
	| NFPA-F = 0		| NFPA-F = 0
	| NFPA-R =		| NFPA-R =
	| NFPA-O = OX		| NFPA-S = OX
	| FlashPt = Non-flammable		| FlashPt = Non-flammable
	}}		}}
	| Section8 = {{Chembox Related		|Section8={{Chembox Related
	| OtherCations = ]<br/>]<br/>]		| OtherCations = ]<br/>]<br/>]
	| OtherAnions = ]<br/>]<br/>]		| OtherAnions = ]<br/>]<br/>]
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	}}		}}
			'''Sodium chromate''' is the ] with the formula Na<sub>2</sub>CrO<sub>4</sub>. It exists as a yellow hygroscopic solid, which can form tetra-, hexa-, and deca]s. It is an intermediate in the extraction of chromium from its ores.
⚫	'''Sodium chromate''' (Na<sub>2</sub>CrO<sub>4</sub>) is a yellow solid ] used as a corrosion inhibitor in the petroleum industry,<ref name=ullmanns>{{Ullmann | author = Gerd Anger, Jost Halstenberg, Klaus Hochgeschwender, Christoph Scherhag, Ulrich Korallus, Herbert Knopf, Peter Schmidt, Manfred Ohlinger | title = Chromium Compounds | doi =10.1002/14356007.a07_067}}</ref> a dyeing auxiliary in the textile industry,<ref name=ullmanns/> as a wood preservative,<ref>{{cite web |url=http://www.pesticideinfo.org/Detail_ChemUse.jsp?Rec_Id=PC34364#ChemID |title=Sodium chromate - Pesticide use statistics for 2005 |accessdate=2008-06-20 |publisher=PAN Pesticides Database}}</ref> and as a diagnostic pharmaceutical in determining ] volume.<ref>{{cite web |url=http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?id=6525 |title=chromitope sodium (Sodium Chromate, Cr 51) injection, solution |accessdate=2008-06-20 |author=Bracco Diagnostics Inc. |publisher=DailyMed}}</ref>
			==Production and reactivity==
	It is obtained from the reaction of ] with ]. It is hygroscopic and can form tetra-, hexa-, and deca]s. Sodium chromate, like other ] compounds, can be ].<ref name=ullmanns/>
			It is obtained on a vast scale by roasting chromium ores in air in the presence of sodium carbonate:
			:2Cr<sub>2</sub>O<sub>3</sub> + 4 Na<sub>2</sub>CO<sub>3</sub> + 3 O<sub>2</sub> → 4 Na<sub>2</sub>CrO<sub>4</sub> + 4 CO<sub>2</sub>
			This process converts the chromium into a water-extractable form, leaving behind iron oxides. Typically ] is included in the mixture to improve oxygen access and to keep silicon and aluminium impurities in an insoluble form. The process temperature is typically around 1100 °C.<ref>{{cite book |url=https://monographs.iarc.fr/ENG/Monographs/vol49/mono49-6B.pdf |title=IARC Monographs 49 Ch. 2 |isbn=9789283212492 }}</ref> For lab and small scale preparations a mixture of chromite ore, sodium hydroxide and sodium nitrate reacting at lower temperatures may be used (even 350 C in the corresponding potassium chromate system).<ref>{{cite journal |title= A new method of potassium chromate production from chromite and KOH-KNO3-H2O binary submolten salt system|author=Zhi Sun, Yi Zhang, Shi-Li Zheng, Yang Zhang |doi=10.1002/aic.11871 |volume=55 |issue = 10|journal=AIChE Journal |pages=2646–2656|year = 2009}}</ref> Subsequent to its formation, the chromate salt is converted to ], the precursor to most chromium compounds and materials.<ref name=ullmanns/> The industrial route to ] involves reduction of sodium chromate with ].
			===Acid-base behavior===
⚫	The substance is a strong ]. It is soluble in water,<ref name="inchem">{{cite web |url=http://www.inchem.org/documents/icsc/icsc/eics1370.htm |title=Sodium chromate |accessdate=2008-06-20 |publisher=inchem}}</ref> producing a weakly basic solution.<ref>{{GESTIS|ZVG=4030|Name=Sodium chromate}}</ref>
			It converts to ] when treated with acids:
			: 2 Na<sub>2</sub>CrO<sub>4</sub> + 2HCl → Na<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub> + 2NaCl + H<sub>2</sub>O
			Further acidification affords ]:
⚫	==See also==
			:Na<sub>2</sub>CrO<sub>4</sub> + H<sub>2</sub>SO<sub>4</sub> → CrO<sub>3</sub> + Na<sub>2</sub>SO<sub>4</sub> + H<sub>2</sub>O
⚫	* ]
			==Uses==
		⚫	Aside from its central role in the production of chromium from its ores, sodium chromate is used as a corrosion inhibitor in the petroleum industry.<ref name=ullmanns>{{Ullmann | author = Gerd Anger, Jost Halstenberg, Klaus Hochgeschwender, Christoph Scherhag, Ulrich Korallus, Herbert Knopf, Peter Schmidt, Manfred Ohlinger | title = Chromium Compounds | doi =10.1002/14356007.a07_067}}</ref> It is also a dyeing auxiliary in the textile industry.<ref name=ullmanns/> It is a diagnostic pharmaceutical in determining ] volume.<ref>{{cite web |url=http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?id=6525 |title=chromitope sodium (Sodium Chromate, Cr 51) injection, solution |access-date=2008-06-20 |author=Bracco Diagnostics Inc. |publisher=DailyMed}}</ref>
			In organic chemistry, sodium chromate is used as an oxidant, converting primary alcohols to ]s and secondary alcohols to ].<ref>] "Δ<sup>4</sup>-cholesten-3,6-dione" Org. Synth. 1955, 35, 36. {{doi|10.15227/orgsyn.035.0036}}</ref> Sodium chromate is a strong oxidizer.
			==Safety==
			As with other ] compounds, sodium chromate is ]ic.<ref name="book100C">{{cite book
			|author = IARC
			|author-link = International Agency for Research on Cancer
			|title = Volume 100C: Arsenic, Metals, Fibres, and Dusts
			|orig-year = 17-24 March 2009
			|url = https://publications.iarc.fr/_publications/media/download/3026/50ed50733f7d1152d91b30a803619022ef098d59.pdf
			|access-date = 2020-01-05
			|date = 2012
			|isbn = 978-92-832-0135-9
			|quote = There is ''sufficient evidence'' in humans for the carcinogenicity of chromium (VI) compounds. Chromium (VI) compounds cause cancer of the lung. Also positive associations have been observed between exposure to Chromium (VI) compounds and cancer of the nose and nasal sinuses. There is ''sufficient evidence'' in experimental animals for the carcinogenicity of chromium (VI) compounds. Chromium (VI) compounds are ''carcinogenic to humans (Group 1)''.
			|publisher = International Agency for Research on Cancer
			|location = Lyon
			|archive-date = 2020-03-17
			|archive-url = https://web.archive.org/web/20200317095517/https://publications.iarc.fr/_publications/media/download/3026/50ed50733f7d1152d91b30a803619022ef098d59.pdf
			|url-status = dead
			}}</ref> The compound is also ] and exposure may produce severe eye damage or blindness.<ref name="MSDS">{{cite web | publisher = JT Baker| title = Potassium dichromate MSDS | url = http://hazard.com/msds/mf/baker/baker/files/p5719.htm}}</ref> Human exposure further encompasses impaired fertility, heritable genetic damage and harm to unborn children.
		⚫	==See also==
		⚫	* ]
	==References==		==References==
	{{Reflist}}		{{Reflist}}
			==Further reading==
⚫	]
		⚫	*{{cite web |url=http://www.inchem.org/documents/icsc/icsc/eics1370.htm |title=Sodium chromate |access-date=2008-06-20 |publisher=inchem}}
⚫	]
			*{{GESTIS|ZVG=4030|Name=Sodium chromate}}
⚫	]
	{{inorganic-compound-stub}}
	{{Sodium compounds}}		{{Sodium compounds}}
			{{Chromates and dichromates}}
		⚫	]
	]
		⚫	]
	]
		⚫	]
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