Hafnium element has 72 protons, 106 neutrons and 72 electrons. Hafnium is a silvery metal at room temperature. The melting point of Hafnium metal is 2233 ̊C. » Common Hafnium compounds: • Hafnium Tetrachloride, HfCl4 • Hafnium(IV) Oxychloride Octahydrate, HfOCl2.8H2O • Hafnium(IV) Fluoride, HfF4 • Hafnium Nitrate, Hf(NO3)4 • Hafnium(IV) Bromide, HfBr4