Atomic Number: 72

Atomic Weight: 178.49

Melting Point: 2506 K (2233°C or 4051°F)

Boiling Point: 4876 K (4603°C or 8317°F)

Density: 13.3 grams per cubic centimeter

Phase at Room Temperature: Solid

Element Classification: Metal

Period Number: 6

Group Number: 4

Group Name: none

Hafnium isotopes have several applications. Hf-180 is used for the production of the radioisotope Hf-181 while Hf-180 is used for the production of the radioisotope Ta-179, which has a medical application. The second isomer of Hf-178 (Hf-178m2) exhibits a very high excitation energy and it has been suggested for use in gamma ray lasers