Sodium stannate
Structural formula | |||||||||||||||||||
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General | |||||||||||||||||||
Surname | Sodium stannate | ||||||||||||||||||
other names |
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Molecular formula |
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Brief description |
white odorless solid |
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properties | |||||||||||||||||||
Molar mass | 212.67 g mol −1 | ||||||||||||||||||
Physical state |
firmly |
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density |
7.3 g cm −3 |
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Melting point |
231.9 ° C |
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boiling point |
2260 ° C |
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Vapor pressure |
1.33 hPa at 1492 ° C |
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solubility |
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safety instructions | |||||||||||||||||||
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Sodium stannate is a sodium - salt of stannic acid . It occurs in different species.
Extraction and presentation
Sodium stannate is obtained by dissolving tin (IV) oxide in excess, concentrated sodium hydroxide solution at about 100 ° C , whereby the trihydrate is formed. The direct melting of tin (IV) oxide and sodium hydroxide creates the anhydrate.
Similarly, sodium stannate can be obtained by reacting tin or tin (IV) sulfide with hot sodium hydroxide solution.
It is also formed when sodium stannite reacts with atmospheric oxygen.
Effective industrial methods are carried out, for example, by reacting sodium carbonate and tin (IV) oxide from cassiterite at around 850 ° C.
properties
Sodium stannate trihydrate is a colorless crystalline powder (thin, six-sided platelets) that is very easily soluble in water, the solubility of which decreases sharply with increasing temperature. It always contains small amounts of adsorbed sodium hydroxide and is very sensitive to carbon dioxide . It has a rhombohedral crystal structure with the space group R 3 (space group no. 148) (a = 5.84 Å , a = 61.2 °) with a superstructure of the cadmium (II) iodide type. The trihydrate cannot be converted into the anhydrate and decomposes at 140 ° C.
use
Sodium stannate is used:
- as a gel former
- for the production of pure tin , other stannates and tin compounds
- as a component of electrolytes for tinning
- as coating material (paper)
The mainly used hexahydroxo salt Na 2 [Sn (OH) 6 ] is also known as sodium hexahydrostannate, sodium hexahydroxostannate, dissecting salt or priming salt. But it can also be understood as the trihydrate of the simple sodium stannate: Na 2 SnO 3 · 3 H 2 O.
Individual evidence
- ↑ entry to SODIUM stannates in CosIng database of the European Commission, accessed on 17 April 2020th
- ↑ a b c d data sheet Sodium tin (IV) oxide hydrate from AlfaAesar, accessed on February 4, 2018 ( PDF )(JavaScript required) .
- ↑ a b c d ( page no longer available , search in web archives ) MP Biomedicals
- ^ A b William M. Haynes: CRC Handbook of Chemistry and Physics, 94th Edition . CRC Press, 2013, ISBN 978-1-4665-7115-0 , pp. 91 ( limited preview in Google Book search).
- ↑ a b Georg Brauer (Ed.) U. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume III, Ferdinand Enke, Stuttgart 1981, ISBN 3-432-87823-0 , p. 1771.
- ↑ Erwin Riedel, Christoph Janiak: Inorganic Chemistry . Walter de Gruyter, 2011, ISBN 978-3-11-022566-2 , p. 552 ( limited preview in Google Book search).
- ↑ a b Ananya Ganguly: Fundamentals of Inorganic Chemistry for Competitive Examinations . ISBN 81-317-7622-0 , pp. 9 ( limited preview in Google Book search).
- ↑ Anil Kumar De: A Text Book of Inorganic Chemistry . New Age International, 2007, ISBN 81-224-1384-6 , pp. 379 ( limited preview in Google Book search).
- ↑ Yuanbo Zhang, Zijian Su, Bingbing Liu, Zhixiong You, Guang Yang, Guanghui Li, Tao Jiang: Sodium stannate preparation from stannic oxide by a novel soda roasting-leaching process. In: Hydrometallurgy. 146, 2014, p. 82, doi: 10.1016 / j.hydromet.2014.03.008 .
- ^ Bernard Moody: Comparative Inorganic Chemistry . Elsevier, 2013, ISBN 978-1-4832-8008-0 , pp. 332 ( limited preview in Google Book search).
- ↑ EChinaChem ( Memento from September 28, 2007 in the Internet Archive )
- ↑ Hans P. Latscha, Helmut A. Klein: Inorganic Chemistry: Chemistry Basics I . Springer, 2007, ISBN 978-3-540-69863-0 ( page 327 in the Google book search).
- ↑ Knowledge: Preparatory Salt ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
- ↑ Dissecting salt . In: Meyers Großes Konversations-Lexikon . 6th edition. Volume 7, Bibliographisches Institut, Leipzig / Vienna 1907, p. 203 .