Element 71
Lutetium
Lanthanides
Lutetium (Lu) is in the d-block of the periodic table — group 3, period 6.
Lutetium is a chemical element with symbol Lu and atomic number 71.
Key data
- Atomic number
- 71
- Atomic mass
- 174.967 u
- Group / Period
- 3 / 6
- Block
- d-block
- Phase at STP
- Solid
- Density
- 9.841 g/cm³
- Melting point
- 1651.8 °C
- Boiling point
- 3401.8 °C
- Electron configuration
- [Xe] 4f14 5d1 6s2
Periodic table block
Lutetium is in the d-block (group 3, period 6). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Petroleum cracking
- •PET scanners
- •Cancer therapy
Discovery
Year: 1907
Discovered by: Georges Urbain
Frequently asked questions
What is the atomic number of Lutetium?
Lutetium has atomic number 71. Its symbol is Lu and its atomic mass is 174.967 u.
What category of element is Lutetium?
Lutetium is classified as lanthanides. It sits in group 3, period 6 of the periodic table.
What block of the periodic table is Lutetium in?
Lutetium is in the d-block (group 3, period 6). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, [Xe] 4f14 5d1 6s2.
What is Lutetium used for?
Common uses of Lutetium include: Petroleum cracking, PET scanners, Cancer therapy.
When was Lutetium discovered?
Lutetium was discovered in 1907 by Georges Urbain.
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