The book of science

Tom Sharp

ParisPaul-Émile Lecoq de Boisbaudran elements


Atomic number 62

Doable stuff

It’s only a coincidence that Lecoq discovered both gallium and samarium, and that the atomic number of samarium is exactly twice the atomic number of gallium.

The history of the discovery of samarium shows us that this stuff isn’t easy. Rare earths are placed in the same locations in the periodic table because they are chemically very similar.

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