Tincture of iodine
Tincture of iodine' is a disinfectant. It has iodine and potassium iodide dissolved in ethanol and water. Normally, iodine does not dissolve in water. But when iodide is added, the iodine can dissolve. Also, ethanol helps iodine dissolve. Tincture of iodine has about equal amounts of iodide and iodine.