Friday, October 4, 2013

Flame Colors in Alkali Metal

Metal                       Color
Lithium                    Crimson
Sodium                    Yellow
Potassium                Lilac
Rubidium                 Red violet
Cesium                    Blue
How the color appear ?          
          The alkali metal or any of its compounds are heated in bunsen flame, the ns' electron gets excited to higher energy levels and while return to their ground state the excitation energy absorbed by them  is released  as light in the visible region. Example: The yellow color of the sodium is a result of the energy emitted when an electrons drops from the 3p1  orbital to the 3s1 orbital of a neutral sodium atom.    

 A      -    Sodium ion in flame.
 B      -    Electron in the excited 3p orbitals.
 C      -    Emitted electron in the excited 3p orbitals to ground 3s state. ( Now the energy released as a                           yellow light)

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