Chapter 20 The Transition Elements Transition elements are those elements in Groups 3-12 in the periodic table. Transistion elements Transition Elements – are the most familiar because they often occur in nature as uncombined elements unlike groups 1 and 2. Transition elements often from colored compounds. Cobalt – Blue Cadmium – Yellow From left to right, aqueous solutions of: Co(NO3)2 (red); K2Cr2O7 (orange); K2CrO4 (yellow); NiCl2 (green); CuSO4 (blue); KMnO4 (purple). Iron, Nickel, and Cobalt They form a unique cluster of transition elements. All three elements are used in the process to create steel and other metal mixtures. Iron – the main component of steel is the mostly widely used of all metals. Copper, Silver, Gold The three elements from Group 11 are so stable, Malleable, (what does this mean?) and are found as free elements in nature that they were used to make coins. They are sometimes referred as the coinage metals. Copper is used in wires Silver is used to make photographic film Gold is used for jewelry and NASA. Zinc, Cadmium, Mercury They are found in Group 12. Zinc is ued to protect or coat objects such as metal. Why? Because Zinc does not rust. Cadmium – is used also in coating metals, but is also used in rechargeable batteries. Mercury – is a silvery, liquid metal – only one at room temp. – is used in thermometers, switches, and batteries. The inner transition metals The two rows of elements that seem to be disconnected from the rest of the periodic table are called the inner transition elements, and they fit in the periodic table between groups 3 & 4. The Lanthanides These elements are called the lanthanide series because they follow the element lanthanum. These elements are used by the motion picture industry to make movies and to produce the colors you see on your TV. (Thank you Lanthanide series) The Actinides These elements are called the actinide series because they follow the element actinium. All of the actinides are radioactive and are unstable. Uranium is an actinide found in the Earth’s crust in usable quantities. Metals in the Crust Earth’s hardened outer layer, called the crust, contains many compounds and a few uncombinded metals such as gold and copper. Metals must be mined and separated from their ores. Most of the world’s platinum is found in South Africa.