Who discovered cerium and when was it isolated?
Jöns Jakob Berzelius and Wilhelm Hisinger isolated a new substance from the mineral cerite in 1803. Martin Heinrich Klaproth made the same discovery independently later that year.
Questions about Cerium
Short answers, pulled from the story.
What are the four allotropic forms of cerium and their temperature ranges?
Four allotropic forms exist at standard pressure labeled alpha to delta. Gamma-cerium is stable below 726 degrees Celsius, beta-cerium exists from room temperature down to minus 150 degrees Celsius, and alpha-cerium forms below minus 160 degrees Celsius.
Which isotopes of cerium occur naturally and what are their abundances?
Naturally occurring cerium consists of four isotopes: Ce-136, Ce-138, Ce-140, and Ce-142. These make up 0.19%, 0.25%, 88.45%, and 11.11% respectively.
How does cerium dioxide function in industrial applications like glass polishing?
Cerium dioxide acts as a catalyst for the combustion of thorium oxide in gas mantles invented by Carl Auer von Welsbach in 1885. It decolorizes glass by converting green-tinted ferrous impurities into nearly colorless ferric oxides and serves chemical-mechanical planarization polishing techniques.
What are the health risks associated with exposure to cerium compounds?
Large doses of cerium nitrate lead to methemoglobinemia though it treats third-degree burns effectively. Fumes from cerium fires are toxic to human lungs and workers exposed to cerium have experienced itching, sensitivity to heat, and skin lesions.