Triiodide is an iodine ion.

The following equilibrium :

I₂ + I^- → I₃^-

gives rise to the triiodide ion in solution. The base is the iodide ion and the acid is Iodine. The reaction is endothermic in nature. I₃(-) has the sp3d3 hybridisation. From low to high concentration, triiodide appears yellow to brown (1).

External links

• Kinetic Study of the iodine-persulfate reaction
• Determination of Hydrogen Peroxide Concentration

Iodine compounds