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Both helium (He) and beryllium (Be) have...

Both helium (He) and beryllium (Be) have two valence electrons.Whereas he represent a noble gas element,Be does no. Assign reason.

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The element He (z=2) has two electrons present in the only shell i.e k hsell since this shell can have a maximum of two electrons only therfore , he is a noble gas e,lement .The elements Be (Z=4) has electronnic configuration as : 2,2 .Although the second shell has also two electrons but it is not complete .It can still acomodate six more electrons .Therefore the element beryllium does not reprsetn a noble gas element.
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