Sodium dihydrogen arsenate

Structural formula
General
Surname	Sodium dihydrogen arsenate
other names	Sodium dihydrogen arsenate (V)
Molecular formula	NaH 2 AsO 4
Brief description	white solid
External identifiers / databases
PubChem	23677060
Wikidata	Q18169404
properties
Molar mass	181.9 g mol −1
Physical state	firmly
density	2.53 g cm −3
safety instructions
H and P phrases	H: 301-331-410
	P: ?
MAK	Switzerland: 0.1 mg m −3 (based on arsenic, measured as inhalable dust )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Sodium dihydrogen arsenate is a chemical compound of sodium from the group of arsenates .

Extraction and presentation

Sodium dihydrogen arsenate monohydrate can be obtained by reacting arsenic acid with sodium hydroxide solution .

{\ displaystyle \ mathrm {H_ {3} AsO_ {4} + NaOH \ longrightarrow NaH_ {2} AsO_ {4} \ cdot H_ {2} O}}

properties

Sodium dihydrogen arsenate is a white solid. When heated, it loses its water of crystallization and from 50 ° C goes via the stages NaH ₂ AsO ₄ → Na ₂ HAsO ₄ → Na ₂ H ₂ As ₂ O ₇ → Na ₃ H ₂ As ₃ O ₁₀ finally above 230 ° C into polymeric sodium metaarsenate NaAsO ₃ over. The dehydration products react with water vapor, whereby the same steps can be detected as in the case of dehydration. The analogous potassium dihydrogen arsenate KH ₂ AsO ₄ , on the other hand, changes into potassium metaarsenate KAsO ₃ without intermediate stages when heated .

Individual evidence

↑ ^a ^b ^c ^d ^e ^f Georg Brauer (Ed.), With the collaboration of Marianne Baudler u. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6 , p. 581.
^ Entry on arsenic compounds in the GESTIS substance database of the IFA , accessed on February 22, 2019 (JavaScript required)
↑ Not explicitly listed in Regulation (EC) No. 1272/2008 (CLP) , but with the specified labeling it falls under the group entry arsenic compounds, with the exception of those named in this appendix in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA) on February 6, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .
↑ Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values (search for 10103-60-3 or sodium dihydrogen arsenate ), accessed on October 24, 2016.
↑ Harry J. Emeleus, JS Anderson: Results and Problems of Modern Inorganic Chemistry . Springer-Verlag, 2013, ISBN 978-3-642-86628-9 , pp. 531 ( limited preview in Google Book search).

[brauer-1] ↑ ^a ^b ^c ^d ^e ^f Georg Brauer (Ed.), With the collaboration of Marianne Baudler u. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6 , p. 581.

[2] Entry on arsenic compounds in the GESTIS substance database of the IFA , accessed on February 22, 2019 (JavaScript required)

[CLP_100.240.769-3] Not explicitly listed in Regulation (EC) No. 1272/2008 (CLP) , but with the specified labeling it falls under the group entry arsenic compounds, with the exception of those named in this appendix in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA) on February 6, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .

[4] Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values (search for 10103-60-3 or sodium dihydrogen arsenate ), accessed on October 24, 2016.

[Harry_J._Emeleus,_J.S._Anderson-5] Harry J. Emeleus, JS Anderson: Results and Problems of Modern Inorganic Chemistry . Springer-Verlag, 2013, ISBN 978-3-642-86628-9 , pp. 531 ( limited preview in Google Book search).