Sodium metaphosphate

Structural formula
General
Surname	Sodium metaphosphate
other names	Maddrel's salt
Molecular formula	(NaPO 3 ) n , n> = 3
Brief description	white odorless solid
External identifiers / databases
CAS number 10361-03-2 EC number 233-782-9 ECHA InfoCard 100.030.699 PubChem 16133893 ChemSpider 10605977 Wikidata Q4291659
properties
Molar mass	g mol −1
Physical state	firmly
density	approx. 2.5 g cm −3
Melting point	approx. 550 ° C
solubility	easily soluble in water (approx. 1000 g l −1 at 20 ° C)
safety instructions
GHS labeling of hazardous substances no GHS pictograms H and P phrases H: no H-phrases P: no P-phrases
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Sodium metaphosphate is a chemical compound of sodium from the group of metaphosphates .

Extraction and presentation

Sodium metaphosphate can be obtained by dehydrating sodium phosphates.

Sodium metaphosphates (NaPO ₃ ) _n as sodium salts of trimeric, tetrameric, optionally also more highly condensed cyclopolyphosphoric acids can be obtained by heating sodium dihydrogen phosphate to above 630.degree .

properties

Sodium metaphosphate is a white, odorless solid that is readily soluble in water. The degradation to orthophosphates takes place more gradually in water and more rapidly in the heat.

use

Sodium metaphosphate is used as an abrasive in toothpaste . Sodium metaphosphates are widely used for water softening, in the textile, paper and photo industries and as a component of detergents and cleaning agents.

See also

• Sodium trimetaphosphate
• Sodium hexametaphosphate

Individual evidence

1. ↑ ^{a b c d e f g h} Entry on sodium metaphosphate in the GESTIS substance database of the IFA , accessed on April 10, 2019(JavaScript required) .
2. ↑ ^{a b} Entry on Sodium Metaphosphate in the Hazardous Substances Data Bank , accessed April 10, 2019.
3. ↑ ^{a b c} Lexicon of Chemistry: Sodium Phosphate - Lexicon of Chemistry , accessed on April 10, 2019.