HM526 Lanthanide and Actinide Elements utorial Questions 1. Name the lanthanide elements in the correct order and write their symbols. 2. What is lanthanide contraction and what are its consequences? 3. In what way are the observed oxidation states of the lanthanides related to their electronic structure 4. In what way does the filling of 4f energy level affect the rest of the periodic table? 5. Name the actinide elements in correct order and write their symbols. 6. Account for the electronic structure of the actinides 7. Contrast the electronic spectra of the lanthanide and transition metal ions. Why do their ions give rise to a very sharp bands in their electronic spectra? 8. Why are the magnetic properties of their complexes little affected by the nature of the ligands? 9. Which actinide isotopes are available in (a) tonnes (b) kilograms (c) gram quantities? 10. What are the main sources of Th and U. and how are these metals obtained? 11. Describe the methods used in separation of isotopes of uranium. Explain the difficulties. 12. Compare and contrast the pyramid of oxidation states found in the first row of transition elements with the oxidation states found in lanthanides and the actinides. 3. Give some typical reactions and comment on the structures of +3 and + in​