Iodine AR
Product code RXSOL-60-6405-100
Iodine
Description
Iodine, a diatomic molecule (I2), is an oxidizing agent and solutions of it are frequently used in chemical analyses. Iodine suffers from low solubility in water and its volatility makes it difficult to handle directly. Both these problems are overcome by the addition of an Iodide salt (usually Potassium Iodide) which forms a Triiodide (I3-) complex with the Iodine. The Triiodide complex is extremely soluble in water and has decreased volatility.
Application
Iodine solutions are typically standardized with Sodium Thiosulfate solutions or Arsenic Trioxide. The equation for reaction with Sodium Thiosulfate is:
I3- + 2 S2O32- → 3 I- + S4O62- (Dithionite ion)
See the Tech Tip under Arsenic Trioxide for information on standardization with Arsenic Trioxide.