Potassium triiodide is a dark brown-violet solution of potassium iodide with iodine in water. A small amount may be used for emergency disinfection of drinking water.
The most commonly used (nominal) 5% solution consists of 5% (wt/v) metallic iodine (I2) and 10% (wt/v) potassium iodide (KI) mixed in distilled water, and has a total iodine content of 126.4 mg/mL. The iodide combines with metallic iodine to form a high concentration of potassium triiodide (KI3) solution. There is some excess potassium.
- Reagent added to the vagina and cervix during colposcopy
- Reagent used to better visualize the mucogingival junction in the mouth
- Oxidizing germicide which is washed off with 70% ethanol solution to avoid scarring and discoloration of the skin
- Reagent used to arrest the flow of blood
- Dye fixative when performing a Gram stain
- Indicator test for the presence of starches in organic compounds
- Cell stain used to make the cell nuclei more visible and to preserve phytoplankton samples
- Reagent used in experiments to observe how a cell membrane uses osmosis and diffusion
- Agent used to help rid the animals of unwanted parasites and harmful bacteria
- Disinfectant to small wounds
- Coloring agent in inks and paints