Atomic Weights and Isotopic Compositions for Carbon
 Isotope   Relative
Atomic Mass 		    Isotopic
  Composition  		 Standard
Atomic Weight 		  Notes 
 
6 C 12   12.0000000(00)   0.9893(8)  [12.0096, 12.0116]  
13   13.003 354 835 07(23)   0.0107(8)
14   14.003 241 9884(40)   

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