| IUPAC name
| Other names
Sulfuric acid, iron(3+) salt (3:2)
|Molar mass|| 399.88 g/mol (anhydrous)|
489.96 g/mol (pentahydrate)
562.00 g/mol (nonahydrate)
|Density|| 3.097 g/cm3 (anhydrous)|
1.898 g/cm3 (pentahydrate)
|Melting point|| 480 °C (896 °F; 753 K) (anhydrous)|
175 °C (347 °F) (nonahydrate)
|Solubility|| Sparingly soluble in alcohol|
Negligible in acetone, ethyl acetate
Insoluble in sulfuric acid, ammonia
|Safety data sheet||Sigma-Aldrich (hydrated)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Iron(III) sulfate also known as ferric sulfate or vitriol of Mars/vitriol martial, is the chemical compound with the formula Fe2(SO4)3, an iron salt.
Ferric sulfate is used in industry as a coagulant for waste.
Addition of a base, like sodium hydroxide to an aqueous solution of ferric sulfate will precipitate iron(III) hydroxide.
Ferric sulfate is a yellow, hygroscopic compound. It is soluble in water, poorly soluble in organic solvents such as acetone, ethanol or various acetates. It is insoluble in sulfuric acid. The anhydrous form melts at 480 °C.
Iron(III) sulfate is available from many chemical suppliers.
One such seller on Amazon sells 4.5 kg of ferric sulfate at 18.40 $.
- 2 FeSO4 + H2SO4 + H2O2 → Fe2(SO4)3 + 2H2O
This method is similar to the one used for obtaining ferric chloride.
n.b. Hydrogen peroxide is also a reducing agent and will reduce Iron(III) to to Iron(II).
- Make Fenton's reagent
- Coagulant for waste water
Ferric sulfate both solid and as solution is corrosive to tissue and metallic objects.
Ferric sulfate should be stored in a tightly closed container, in a cool, dry place.
Ferric sulfate can be neutralized with slaked lime.