What is Potassium iodide?
[[File:Potassium iodide.jpg|thumb|Potassium iodide]] '''Potassium iodide''' is a [[chemical compound]]. Its chemical formula is KI. It has [[potassium]] and [[iodide]] [[ion]]s in it. ==Properties== It is a colorless [[crystalline]] solid. It is a weak [[reducing agent]]. It reacts with [[chlorine]] to make [[iodine]] and [[potassium chloride]]. It turns yellow when in air. This is because it reacts with [[oxygen]] and [[carbon dioxide]] to make iodine and [[potassium carbonate]]. It reacts with iodine to make the triiodide ion. That is why a solution of potassium iodide dissolves iodine. ==Preparation== It is made by reacting iodine or [[hydriodic acid]] with potassium hydroxide. ==Uses== It is used to supply iodine in the form of vitamin tablets or pills. It can be added to [[table salt]] to prevent a [[wikt:deficiency|deficiency]] of iodine. It is also used to make [[silver iodide]]. It can be used to add iodine to [[organic chemistry|organic]] compounds. It is used to prevent [[thyroid]] [[cancer]] by filling up the thyroid with normal iodine. After a nuclear explosion there normally is radioactive iodine in the air. The radioactive iodine collects in the thyroid and causes cancer. When the person takes potassium iodide it fills up the thyroid with iodine so no radioactive iodine can come in. ==Related pages== *[[Potassium chloride]] *[[Potassium nitrate]] {{Cough and cold preparations}} {{Antifungals}} {{chem-stub}} [[Category:Potassium compounds]] [[Category:Iodine compounds]]