Question

Which of the following elements are not transition metals?

• A. Cu, Ag, Au
• B. Zn, Hg, Cd
• C. Sc, Ti, V
• D. Fe, Co, Ni

Answer 1

The correct option is B Zn, Hg, Cd

According to IUPAC, transition metals are defined as metals which have incomplete d subshell either in neutral atom or in their ions. Zinc, cadmium and mercury of group 12 have full $d^{10}$ configuration in their ground state as well as in their common oxidation states and hence, are not regarded as transition metals. However, being the end members of the 3d, 4d and 5d transition series, respectively, their chemistry is studied along with the chemistry of the transition metals.