![]() For this eye in the sky, NASA chose the rare metal beryllium (Beh-RIL-ee-um) to make its honeycomb of gold-plated mirrors. After 25 years in development, the telescope launched on Christmas morning in 2021. ![]() Sometimes, a special project - such as the $10-billion James Webb Space Telescope - may call for a fairly rare metal. But if we wanted pure sodium, we’d need a way to separate it from one of the chemicals to which it had bonded. For example, silver can be mined as pure silver. They often occur naturally in forms easy to work with. And that highlights another reason low-reactivity metals are so useful. Sodium chloride, or table salt, is a common example. Instead, we find it after it has already bonded chemically with one or more other elements. Good thing, then, that pure sodium never occurs naturally. Watch as the ingredients of table salt - sodium (a metal) and chlorine - react chemically. But pure sodium, also a metal, is so reactive it explodes on contact with water! Pure silver is so safe that we use it for jewelry and flatware. Low-reactivity metals are safer to handle than high-reactivity ones. Reactivity refers to how easily a substance reacts chemically with other substances. (Although most known elements are metals, they are fairly uncommon in nature.)įamiliar metals also are less reactive than most other metals. For one thing, they’re easier to find than other metals. ![]() Although more than three-fourths of the 118 elements on the periodic table are metals, we craft tools from only a few of these. That’s because familiar metals, such as iron and silver, are special. Being malleable (MAAL-ee-ah-bul), metals can be hammered into sheets without shattering. Because they’re ductile (DUK-tul), they can be easily pulled and stretched into wires without snapping. Metals also can conduct electricity.īut not all metals are equally prized. A towering skyscraper bends under a strong gust of wind, but it doesn’t snap.
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