From ProofWiki
Jump to navigation Jump to search

Chemical Element

Rubidium is the chemical element that has $37$ protons in the nuclei of its atoms

Its chemical symbol is $\text {Rb}$.



Rubidium-$87$ is the isotope of rubidium which has $50$ neutrons in addition to its $37$ protons.

Rb-$87$ is radioactive, with a half-life of approximately $48.8 \times 10^9$ years.

Linguistic Note

The word rubidium derives from the Latin word rubidus, meaning deep red, after the colour of the lines in its emission spectrum.