video tutorial Fremy's salt and a chemical mystery

Name: video tutorial - Fremy's salt and a chemical mystery
Uploaded: 2025-12-11T09:03:44.071Z
Duration: 9 min 48 s
Description: We'll save that for a future video. This is the potassium hydroxylamine disulfonate which we prepared in a previous video....So we've weighed out 1 gram of potassium permanganate crystals.

Describes testing potassium hydroxylamine disulfonate by attempting to synthesize Fremy’s salt via oxidation with potassium permanganate.
Dissolves the starting material in warm water, forms a green‑blue reaction with permanganate and a manganese dioxide precipitate; after filtration, the blue filtrate is obtained.
Chilling the filtrate yields yellow crystalline material that dries to a light brown powder (2.2 g), which does not match manganese dioxide or the expected salt.
Various tests on the brown solid show color changes and solubility behavior that do not identify it as MnO2 or sodium bisulfite, suggesting a mixture of compounds with a distinctive color.
Overnight storage in a sealed bag converts the material to a white powder with traces of brown; dissolution in water yields a lilac solution and an orange solid, which gradually dissolves and the solution fades to colorless.
The presenters speculate the orange solid might be Fremy’s salt and question the identity of the intermediate; acknowledge ambiguity and potential issues with the hydroxylamine OTC route, and invite viewers to stay tuned for answers and a Kimpletor contest prize.