CAS Registry Number

CAS 20816-12-0 — Osmium tetroxide

Osmium tetroxide is a highly toxic, volatile inorganic compound used primarily as a stain in electron microscopy to enhance contrast in biological samples, as well as a catalyst in organic synthesis. It is a powerful oxidizing agent with a distinctive pungent odor. CAS 20816-12-0, molecular formula OsO4, molecular weight 254.23 g/mol. Must be stored between 2–8°C in a tightly sealed, airtight container under inert gas. Signal word: Danger. Molekula supplies osmium tetroxide from research to bulk quantities with full documentation and ISO 9001:2015 traceability.