CrO3, or chromium trioxide, is a chemical compound composed of chromium and oxygen. It appears as a dark red to black solid and is highly soluble in water. CrO3 is primarily used in the production of chromium salts and as an oxidizing agent in various chemical reactions. Due to its strong oxidizing properties, CrO3 is also utilized in the manufacturing of dyes, pigments, and in the leather tanning process. However, it is important to handle CrO3 with care, as it is toxic and can pose health risks if inhaled or ingested.