Sodium hexametaphosphate

Sodium hexametaphosphate

Names
Other names Calgon S Glassy sodium Graham's salt Hexasodium metaphosphate Metaphosphoric acid, hexasodium salt SHMP Sodium polymetaphosphate
Properties
Chemical formula	(NaPO3)6
Molar mass	611.7704 g/mol
Appearance	Crystalline solid
Density	2.484 g/cm3
Melting point	628 °C (1,162 °F; 901 K)
Boiling point	1,500 °C (2,730 °F; 1,770 K)
Solubility in water	Soluble
Solubility	Insoluble in organic solvents
Hazards
Safety data sheet	Sigma-Aldrich
Lethal dose or concentration (LD, LC):
LD50 (Median dose)	3,053 mg/kg (rat, oral)
Related compounds
Related compounds	Phosphoric acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Sodium hexametaphosphate or sodium polymetaphosphate is a chemical compound, a hexamer with the formula (NaPO₃)₆.

Properties

Chemical

Sodium hexametaphosphate hydrolyzes in aqueous solution, particularly under acidic conditions, to sodium trimetaphosphate and sodium orthophosphate.

Physical

Sodium hexametaphosphate is a hard crystalline solid, insoluble in most solvents.

Availability

Sodium hexametaphosphate is sold in many hardware stores as water deflocculant.

Preparation

Sodium hexametaphosphate can be made by dehydrating monosodium phosphate to sodium acid pyrophosphate and then to sodium hexametaphosphate.

Projects

• Water filtration
• Make elemental phosphorus

Handling

Safety

Sodium hexametaphosphate has low toxicity and doesn't require special handling.

Storage

In closed bottles.

Disposal

No special disposal is required. Discard it as you wish.

References

Relevant Sciencemadness threads

• Questionable Synth:Sodium Metasilicate