Element 101
Mendelevium
Actinides
Mendelevium (Md) is in the f-block of the periodic table — group 3, period 7.
Mendelevium is a synthetic element with chemical symbol Md (formerly Mv) and atomic number 101.
Key data
- Atomic number
- 101
- Atomic mass
- 258.000 u
- Group / Period
- 3 / 7
- Block
- f-block
- Phase at STP
- Solid
- Density
- —
- Melting point
- 826.9 °C
- Boiling point
- —
- Electron configuration
- [Rn] 5f13 7s2
Periodic table block
Mendelevium 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
- •Research only
- •Atomic-scale studies
- •Named after Mendeleev
Discovery
Year: 1955
Discovered by: Lawrence Berkeley National Laboratory
Frequently asked questions
What is the atomic number of Mendelevium?
Mendelevium has atomic number 101. Its symbol is Md and its atomic mass is 258 u.
What category of element is Mendelevium?
Mendelevium is classified as actinides. It sits in group 3, period 7 of the periodic table.
What block of the periodic table is Mendelevium in?
Mendelevium 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] 5f13 7s2.
What is Mendelevium used for?
Common uses of Mendelevium include: Research only, Atomic-scale studies, Named after Mendeleev.
When was Mendelevium discovered?
Mendelevium was discovered in 1955 by Lawrence Berkeley National Laboratory.
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