who discovered it?
Robert Bunsen and Gustav Kirchhoff
Introduction
German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. 
where is rubidium found on the periodic table It is the 37th element. what letters are used to represent it? Rb
Robert Bunsen and Gustav Kirchhoff Robert Bunsen and Gustav Kirchhoff Robert Bunsen , Gustav Kirchhoff
Rubidium Rubidium Rubidium
History History Introduction
Rubidium was discovered in 1861 by Robert Bunsen and Gustav Kirchhoff, in Heidelberg, Germany, in the mineral lepidolite through flame spectroscopy.  Rubidium was discovered in 1861 by Robert Bunsen and Gustav Kirchhoff German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. 
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Rubidium [SEP] Introduction
German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms. Rubidium is not a known nutrient for any living organisms. However, rubidium ions have the same charge as potassium ions and are actively taken up and treated by animal cells in similar ways.