Group 4 element

In modern IUPAC nomenclature, Group 4 of the periodic table contains the following chemical elements:

• titanium (Ti)
• zirconium (Zr)
• hafnium (Hf)
• rutherfordium (Rf).

This group lies in the transition metals.

These elements are hard alloys. All isotopes of rutherfordium are radioactive, and have been synthesized in the laboratory, none of them have been found occurring in nature.

Biological occurances

The group 4 elements are not known to be involved in the biological chemistry of any living systems. They are hard refractory metals with low acqueous solubility and low availability to the biosphere. Titanium is one of the few first row d-block transition metals with no known biological role. Rutherfordium's radioactivity would make it toxic to living cells.