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Skyscrapers, Neon Lights, and the Periodic Table - page 18 / 30





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Uses of Transition Elements Most transition metals have higher melting points than the representative elements. The fil- aments of lightbulbs, like the one in Figure 14, are made of tungsten, element 74. Tungsten has the highest melting point of any metal (3,410°C) and will not melt when a current passes through it.

Mercury, which has the lowest melting point of any metal (39°C), is used in thermometers and in barometers. Mercury is the only metal that is a liquid at room temperatures. Like many of the heavy metals, mercury is poisonous to living beings. Therefore, mercury must be handled with care.

Chromium’s name comes from the Greek word for color, chroma, and the element lives up to its name. Two substances containing chromium are shown in Figure 15. Many other tran- sition elements combine to form substances with equally bril- liant colors.

Ruthenium, rhodium, palladium, osmium, iridium, and platinum are sometimes called the platinum group because they have similar properties. They do not combine easily with other elements. As a result, they can be used as catalysts. A catalyst is a substance that can make something happen faster but is not changed itself. Other transition elements, such as nickel, zinc, and cobalt, can be used as catalysts. As catalysts, the transition elements are used to produce electronic and consumer goods, plastics, and medicines.

Figure 14 The transition metal tungsten is used in lightbulbs because of its high melting point.

Figure 15 Transition metals are used in a variety of products.

Transition Metals

SECTION 3 Transition Elements K


(t)Geoff Butler, (b)Royalty-Free/CORBIS

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