Sodium diphosphate
Structural formula | |||||||||||||||||||
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General | |||||||||||||||||||
Surname | Sodium diphosphate | ||||||||||||||||||
other names |
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Molecular formula | Na 4 P 2 O 7 | ||||||||||||||||||
Brief description |
white odorless solid |
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External identifiers / databases | |||||||||||||||||||
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properties | |||||||||||||||||||
Molar mass | 265.90 g mol −1 | ||||||||||||||||||
Physical state |
firmly |
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density |
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Melting point |
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solubility |
slightly soluble in water (60 g l −1 at 20 ° C) |
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safety instructions | |||||||||||||||||||
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MAK |
Switzerland: 5 mg m −3 (measured as inhalable dust ) |
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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 diphosphate or sodium pyrophosphate is a colorless sodium salt of diphosphoric acid . It belongs to the diphosphates and has the empirical formula Na 4 P 2 O 7 . The name diphosphate is occasionally used in place of tetrasodium diphosphate . Diphosphates are also parts of organic compounds such as adenosine diphosphate . As a food additive , tetrasodium diphosphate is known as E 450c.
presentation
The pyrophosphate can be obtained by heating disodium hydrogen phosphate at 500 ° C for several hours :
use
In detergents and dishwashing detergents and toothpaste as an emulsifier for fats and oils and water softeners , in baking powder, in cheese preparation. It is also used to stabilize hydrogen peroxide .
The decahydrate is used as a dispersant for a sludge analysis according to DIN EN ISO 17892-4.
Individual evidence
- ↑ Entry on TETRASODIUM PYROPHOSPHATE in the CosIng database of the EU Commission, accessed on April 17, 2020.
- ↑ a b c d e f g h Entry on sodium pyrophosphate in the GESTIS substance database of the IFA , accessed on February 1, 2016(JavaScript required) .
- ↑ Swiss Accident Insurance Fund (Suva): Limit Values - Current MAK and BAT values (search for 7722-88-5 or tetrasodium pyrophosphate ), accessed on March 4, 2020.
- ^ RN Bell: Sodium pyrophosphates (Sodium diphosphates) . In: Ludwig F. Audrieth (Ed.): Inorganic Syntheses . tape 3 . McGraw-Hill, Inc., 1950, pp. 98-101 (English).