Ytterbium atomic weight

Atomic number 71 Standard state Lu (c) Ytterbium Atomic weight 175.0... 

Having obtained 10 kg of euxenite from Norway, Nilson could prepare oxides of both ytterbium and scandium in quantities large enough for atomic weight determinations. His values were 173 for ytterbium and 44 for scandium. Modem atomic weights are 173.04 and 44.96 respectively. 

The international committee for atomic weights decided in 1909 to give Urbain the priority, but changed the name neoytterbium to ytterbium and lutecium to lutetium. 

The isotopic composition and atomic weight of ytterbium. Int. J. Mass Spectrom., 252 (3), 222—227. 

Density The density depends upon the atomic weight, atomic radius and the structme of the aggregate. It is a general trend in a periodic family that density increases with increase in atomic weight. This trend is observed in lanthanides also. The reason is that the increase in atomic weights in lanthanides is comparatively larger than the increase in volumes of individual atoms, since the lanthanides have almost the same atomic radii. The exceptions are europium (Eu) and ytterbium (Yb). 

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