Iodide - does it quickly decompose when exposed to ambient light?

[ZoWhat]

Here's my storage container

Here's my specimen cup I pour the Iodide into so a can quickly suck up 10ml into a syringe for dosing

Here's my DT room with four NE facing windows providing plenty of ambient sunlight

QUESTION:
Is me keeping a couple weeks worth of Iodide in a semi-clear specimen cup to dose out quickly being decomposed by the ambient sunlight in my DT room?


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[Randy Holmes-Farley Verified Community Expert]

Some iodide will air oxidize to I2 with or wiithout light to I2 (a component of Lugols).

Oxidation of Potassium Iodide by Hydrogen Peroxide

Department of Chemistry & Chemical Biology, The School of Arts and Sciences, Rutgers, The State University of New Jersey

chem.rutgers.edu

"Stock solution 1.0 M potassium iodide, KI: Dissolve 33.2 g KI in 160 mL distilled water – dilute to 200 mL. (The iodide ions in this solution will be oxidized slowly by oxygen in the air. The product is molecular iodine, I2, which darkens the solution. This air oxidation can be retarded by preparing the solution with water that has been deoxygenated by boiling or by passing nitrogen gas through it, and then storing the solution in an air tight container.)"

 

[ZoWhat]

Wondering if most elements that ppl dose are already decomposing bc of poor storage habits due to air/temp/light

 

[Randy Holmes-Farley Verified Community Expert]

Wondering if most elements that ppl dose are already decomposing bc of poor storage habits due to air/temp/light

Most elements we dose do not have such instabilities (calcium, alk, magnesium, potassium, nitrate, phosphate).

Some of the trace elements are unstable toward air oxidation. Iron solutions, for example. That's why I try to steer folks away from adding them at high dilution to top off water, etc.