Ferroin
| Names | |
|---|---|
| IUPAC name
1,10-phenanthroline iron(II)
| |
| Other names
1,10-Phenanthroline iron(II) sulfate complex
Ferroin indicator solution MFCD00036428 | |
| Properties | |
| C36H24FeN62+ (cation) [Fe(o-phen)3]SO4 (sulfate) | |
| Molar mass | 596.27 g/mol (cation) 692.5 g/mol (sulfate) |
| Appearance | Blood-red liquid (solution) |
| Odor | Odorless |
| Density | 0.999 g/mL at 25 °C (0.1% solution) |
| Melting point | Decomposes above 60 °C (solution) |
| Boiling point | Decomposes |
| Soluble | |
| Solubility | Insoluble in hydrocarbons |
| Vapor pressure | ~0 mmHg |
| Hazards | |
| Safety data sheet | Sigma-Aldrich (0.1 % solution) |
| Related compounds | |
| Related compounds
|
Phenanthroline |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Ferroin is the chemical compound with the formula [Fe(o-phen)3]SO4, where o-phen is an abbreviation for 1,10-phenanthroline, a bidentate ligand. The term "ferroin" is used loosely and includes salts of other anions such as chloride.
Contents
Properties
Chemical
Ferroin is used as an indicator in analytical chemistry. The active ingredient is the [Fe(o-phen)3]2+ ion, which is a chromophore that can be oxidized to the ferric derivative [Fe(o-phen)3]3+. The potential for this redox change is +1.06 volts in 1 M H2SO4. It is a popular redox indicator for visualizing oscillatory Belousov–Zhabotinsky reactions.
Ferroin is suitable as a redox indicator, as the color change is reversible, very pronounced and rapid, and the ferroin solution is stable up to 60 °C.
Physical
The aq. solution of ferroin is a dark red liquid, odorless, which changes color in oxidizing medium.
Availability
Ferroin is sold by chemical suppliers.
Preparation
Ferroin sulfate may be prepared by mixing an aq. solution of phenanthroline with one of iron(II) sulfate.
- 3 o-phen + Fe2+ → [Fe(o-phen)3]2+
Projects
- Belousov–Zhabotinsky reaction
- Make fake blood
- COD titration indicator
Handling
Safety
Ferroin has low toxicity, though it may be irritant. It tens to stain, which are not very easy to remove.
Storage
In closed dark amber bottles, away from oxidizing agents and acids.
Disposal
Ferroin should be strongly diluted before being poured down the drain.
