Iodine Standardized Solutions

Most of the world’s iodine is mined in Chile’s Atacama Desert, followed by Japan. In Chile it is an ore (caliche ore), but in Japan it is present as a brine, deep underground. But even in these deposit sources the iodine content is very small- less than 0.1%. As far back as 1852 it was hypothesized (and later proven) that iodine deficiency causes Goiter, a thyroid disease. Today, it is added to table salt as a supplement. Other uses include CAT scan technology, X-rays, nuclear imaging, and tracing of faults in machinery.

Iodine is used in redox titrations for analytical chemistry. One way to standardize iodine is with sodium thiosulfate which has been tested against a primary standard of potassium dichromate. This is preferred over direct analysis with arsenic trioxide , due to the toxicity of arsenic, although a direct comparison to arsenic is most accurate as it eliminates the use of a secondary standard.

As a halogen, iodine has a relatively high volatility, although much less than fluorine and chlorine. It is solid at room temperature, but it evaporates by going from solid directly to gas via sublimation. Because of the volatile nature of iodine solutions, the containers should be capped immediately after dispensing the solutions. These solutions also must be re-standardized periodically, to verify the concentration for accurate wet chemistry results.

Exaxol carries a full line of iodine volumetric solutions, with most of them stocked and ready to ship with a quick turnaround. These solutions are made and tested in our ISO 17025 accredited laboratory.