Element 72
Hafnium
Transition metals
Hafnium (Hf) is in the d-block of the periodic table — group 4, period 6.
Hafnium is a chemical element with symbol Hf and atomic number 72.
Key data
- Atomic number
- 72
- Atomic mass
- 178.492 u
- Group / Period
- 4 / 6
- Block
- d-block
- Phase at STP
- Solid
- Density
- 13.31 g/cm³
- Melting point
- 2232.8 °C
- Boiling point
- 4602.9 °C
- Electron configuration
- [Xe] 4f14 5d2 6s2
Periodic table block
Hafnium is in the d-block (group 4, 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
- •Nuclear control rods
- •Plasma cutting
- •Microchips
Discovery
Year: 1923
Discovered by: Dirk Coster
Frequently asked questions
What is the atomic number of Hafnium?
Hafnium has atomic number 72. Its symbol is Hf and its atomic mass is 178.492 u.
What category of element is Hafnium?
Hafnium is classified as transition metals. It sits in group 4, period 6 of the periodic table.
What block of the periodic table is Hafnium in?
Hafnium is in the d-block (group 4, period 6). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, [Xe] 4f14 5d2 6s2.
What is Hafnium used for?
Common uses of Hafnium include: Nuclear control rods, Plasma cutting, Microchips.
When was Hafnium discovered?
Hafnium was discovered in 1923 by Dirk Coster.
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