Tellurium fundamental properties

Some of the fundamental properties of sulfur, selenium and tellurium differ significantly from those of oxygen, giving rise to disparities between the structures and properties of heavier chalcogen-nitrogen molecules and ions compared to those of their N-O counterparts. The major contributors to these differences include the following ... 

From these results Moseley suggested that one proton (and therefore one electron) was added to the atom on going from one element to the next. Atomic number was therefore a more fundamental property of atoms than relative atomic mass. When the elements are arranged in order of atomic number the problems of elements being in the wrong order , for example iodine and tellurium, are removed. Moseley published his findings in 1914, but died in the First World War. 

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