Potassium iodide starch paper

Schematic representation of the complex between I ₃ ^- and strength

Potassium iodide starch paper is a filter paper that has been impregnated with potassium iodide and starch . It is used to detect oxidizing agents such as B. hydrogen peroxide , peracids , peroxides or nitrous acid . When the oxidizing agent is detected , the iodide is oxidized to elemental iodine , which turns brown. The formation of a charge transfer complex of the iodine molecule as I ₃ ^- and intercalation into the helical structure of the starch contained in the paper increases the sensitivity of the detection reaction considerably. In contrast to the pure brown iodine, the resulting complex has a purple color.

See also

• Iodine sample

literature

• Gerhart Jander, Ewald Blasius, Joachim Straehle, Eberhard Schweda; Textbook of analytical and preparative inorganic chemistry, Hirzel S. Verlag ISBN 377760612X