Practice Problem 11

Predict the group in the periodic table in which element 114 belongs.  What oxidation states are expected for this element?

Solution

We can use the aufbau principle to predict the following electron configuration for element 114:

1s²2s²2p⁶3s²3p⁶3d¹⁰4p⁶5s²4d¹⁰5p⁶6s²4f¹⁴5d¹⁰6p⁶7s²5f¹⁴6d¹⁰7p²

This configuration can be abbreviated as follows:

X = [Rn] 7s²5f¹⁴6d¹⁰7p²

In chapter 8, we concluded that filled d and f subshells are ignored when valence electrons on an atom are counted.  Thus, the valence electrons for this element are the 7s² and 7p² electrons.  The element therefore belongs in Group IVA, directly below Pb.   Possible oxidation states are +2 and +4.