Column Descriptions Relative Isotopic Standard Isotope Atomic Mass Composition Atomic Weight Notes _________________________________________________________________________ 70 Yb 168 167.9338896(22) 0.00123(3) 173.054(5) g 170 169.9347664(22) 0.02982(39) 171 170.9363302(22) 0.1409(14) 172 171.9363859(22) 0.2168(13) 173 172.9382151(22) 0.16103(63) 174 173.9388664(22) 0.32026(80) 176 175.9425764(24) 0.12996(83) _________________________________________________________________________NIST | Physical Measurement Laboratory | Physical Reference Data | Atomic Weights and Isotopic Compositions Main Page