Web Elements
Web Elements Periodic Table: Holmium
Provides a great deal of elemental information about the chemical element holmium. There are audio files demonstrating the correct pronunciation of the element name, pictures showing the electron shells, information on isotopes,...
Science Struck
Science Struck: Inner Transition Metals
Discusses the organization of the periodic table into periods and groups, then looks at where the Lanthanoids and Actinoids are situated, and their properties.