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General Chemistry

Curium

Definition and meaning of Curium in chemistry.

Curium is a synthetic transuranic element with the symbol Cm and atomic number 96. It is a radioactive, hard, silvery metal named in honor of scientists Marie and Pierre Curie.

In more detail

Curium is an intensely radioactive actinide element that rapidly oxidizes in air to form a thin surface layer. It is synthesized by bombarding plutonium or americium with neutrons or alpha particles in nuclear reactors and particle accelerators. The element strongly favors the +3 oxidation state in its compounds, aligning its chemistry closely with that of its lanthanide homologue, gadolinium. Due to its position in the f-block, curium exhibits unique magnetic properties, transitioning to an antiferromagnetic state at very low temperatures. The extreme radioactivity of curium generates substantial decay heat, causing the pure metal to glow purple in the dark.

Key facts

FieldGeneral Chemistry
SymbolCm
Atomic number96
Atomic mass[247] u
CategoryActinide
State at room temperatureSolid
Year discovered1944
Notable propertyGenerates extreme decay heat
Example

Curium-244 serves as an alpha particle source in the alpha particle X-ray spectrometers used on several Mars rovers to analyze the composition of Martian rocks.

Frequently asked questions

Why does curium glow in the dark?

The intense alpha radiation emitted by curium isotopes excites the surrounding air molecules and the metal itself, producing visible thermal and radioluminescent light.

Is curium useful for generating nuclear power?

While curium isotopes generate significant heat, they are not typically used in power generation due to the difficulties and hazards associated with their intense neutron and gamma emissions.

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