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Hydrogen is not in the first group as it was before and it is now placed above the periodic table? So why is it still categorized as a metal in some books?


marked as duplicate by Ben Norris, Jon Custer, Todd Minehardt, Klaus-Dieter Warzecha, A.K. Jul 23 '16 at 23:32

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  • $\begingroup$ Which books will categorize a reactive gas as a metal? Theoretically there does seem to be metallic hydrogen, but so far experimental efforts to produce a sample have either failed or returned questionable results. $\endgroup$ – CuriousOne Jul 23 '16 at 8:31

There is a lot that could be said about this question, but a simple explanation goes like this:

  • Some periodic tables categorize hydrogen as a metal (or at least an alkali metal) because it has one electron in its outermost orbital - just like Lithium, Sodium, Potassium, etc., which are obviously metals.

  • Other authors of chemistry textbooks realize that hydrogen seems to love the gas-phase so much over the solid phase that it just doesn't make sense to call it a metal, irrespective of what atomic orbital pattern may tell us.

Hence the differences between authors of texts and where they put Hydrogen on their periodic table.


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