Question

i) Separation of lanthanide elements is difficult. Explain.
ii) Sm2+, Eu2+ and Yb2+ ions in solutions are good reducing agents but anaqueous solution of Ce4+ is a good oxidizing agent. Why?

Answer 1

(i) Separation of lanthanide elements is difficult Because all lanthanide's have almost similar physical as well as chemical properties.
(ii) In lanthanide series the common oxidations state is +3.
Sm2+,Eu2+and Yb2+ ions in solution get oxidised by loosing electron so act as good reducing agents. While Ce4+ in aqueous solution to acquire 3+ gain an electron and get reduced so act as oxidising agent.