Rubidium is a alkali metal. It was one of the four elements discovered by the spectroscope. Bunsen and Kirchoff used a spectroscope to find rubidium in a mineral called lepidolite. When the two scientists heated the sample of lepidolite, they found two new lines, which were a dark red color and named it rubidium from the word rubidus, which served to designate the deepest red by ancient civilizations. The rubidium concentration in the lepidolite had been so tiny that Bunsen and Kirchhoff needed to use one hundred and fifty kilograms of the ore to extract enough metal to study its properties.
Rubidium is a soft, silvery-white metallic element. It can ignite in the air and reacts violently with water. Rubidium is a relatively abundant element at about 35 to 75 parts per million. It is about as abundant as nickel, chromium, zinc and copper. It has a melting point of 39 C (102) and a boiling point of 688 C (1,270 F). Its density is 1.532 grams per cubic centimeter. A common method for producing rubidium is to pass an electrical current through molten rubidium chloride.
Rubidium has many uses in today’s world. It is used to make atomic clocks. These clocks are extremely precise and are used when precise time keeping is needed. It is also used to make photocells. A photocell is a device for converting light energy into electrical energy. The isotope Rubidium-87 is slightly radioactive and has been used in the dating of rocks. Also Rubidium salts are used in glasses and ceramics.
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