Actinides

Options

A. are all synthetic elements
B. include elements 104
C. have any short lived isotopes
D. have variable valency

Answer

D

Explanation

All actinides show different oxidation state such as `+2, +3, +4, +5` and `+7`. However, `+3` oxidation state is most common among all the actinides. The wiide range of oxidation states of actinides is attributed to the fact that the 5f, 6d and 7s energy levels are of comparable energies. Therefore, all these three sub-shells can participate.