Atomic Weights and Isotopic Compositions for Sodium
Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
_________________________________________________________________________
11  Na  23   22.9897692820(19)  1             22.98976928(2)    
_________________________________________________________________________

NIST | Physical Measurement Laboratory | Physical Reference Data | Atomic Weights and Isotopic Compositions Main Page