The Period 6 Transition Metals Have Greater Densities Than Either

Short Answer

The period 6 transition metals have greater densities than either the period 4 or 5 transition metals.An explanation concerns the 4f orbitals,which are filled with electrons just prior to the 5d orbitals.As the 4f orbitals are filled,the radii of the elements decrease.The decrease in size is referred to as the ________ contraction.