Element 96
Curium
Actinides
Curium (Cm) is in the f-block of the periodic table — group 3, period 7.
Curium is a transuranic radioactive chemical element with symbol Cm and atomic number 96.
Key data
- Atomic number
- 96
- Atomic mass
- 247.000 u
- Group / Period
- 3 / 7
- Block
- f-block
- Phase at STP
- Solid
- Density
- 13.51 g/cm³
- Melting point
- 1339.8 °C
- Boiling point
- 3109.8 °C
- Electron configuration
- [Rn] 5f7 6d1 7s2
Periodic table block
Curium is in the f-block (group 3, period 7). Elements land in the f-block when their highest-energy electrons fill an f subshell — these are the lanthanides and actinides shown beneath the main table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Mars rover power source
- •Research only
- •Radioactive
Discovery
Year: 1944
Discovered by: Glenn T. Seaborg
Frequently asked questions
What is the atomic number of Curium?
Curium has atomic number 96. Its symbol is Cm and its atomic mass is 247 u.
What category of element is Curium?
Curium is classified as actinides. It sits in group 3, period 7 of the periodic table.
What block of the periodic table is Curium in?
Curium is in the f-block (group 3, period 7). Its highest-energy electrons occupy the f subshell — you can see this in its electron configuration, [Rn] 5f7 6d1 7s2.
What is Curium used for?
Common uses of Curium include: Mars rover power source, Research only, Radioactive.
When was Curium discovered?
Curium was discovered in 1944 by Glenn T. Seaborg.
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