21. About 10 % of the lanthanide contraction has been attributed to relativistic effects. 22. Lutetium is the hardest and densest lanthanide and has the highest melting point. 23. Hydrides in the transition metals and lanthanides are also typically polymeric covalent hydrides. 24. Like the lanthanides , the actinides form a family of elements with similar properties. 25. Lanthanum is the least volatile of the lanthanides . 26. Samarium is one of the few lanthanides that exhibit the oxidation state + 2. 27. Without the lanthanide contraction, a chemical separation of lanthanides would be extremely difficult. 28. Without the lanthanide contraction, a chemical separation of lanthanides would be extremely difficult. 29. This behavior is known as the lanthanide contraction. 30. Homogeneous assays rely on direct coupling of the lanthanide label with an organic acceptor.
