Rubidium (Rb) is a chemical element with atomic number (Z) 37, group 1, period 5, and atomic weight 85.468. The Rubidium (Rb) is a soft, silvery-white metallic element of the alkali metals group that is the most electropositive and alkaline elements, used in the manufacture of photocells and in the removal of residual gases from vacuum tubes. (Refer to the Chemical Element; Periodic Table)
