The elements of the 3rd period of the periodic table are given along:

Na Mg Al Si P S Cl


(a) Which is more non-metallic S or Cl?


Na Mg Al Si P S Cl


(b) Which has a higher atomic mass: Al or Cl?

(a) Along the group non-metallic character increases so; Cl (Chlorine) is more non-metallic.

(b) As we see the trend as the atomic no. increases atomic mass also increases (other than few exceptions). So, Cl has a higher atomic mass than Al.


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