The following Lewis diagram represents the valence electron configuration of a main-group element. :X: This element is in group According to the octet rule, this element would be expected to form an ion with a charge of If X is in period 3 , the ion formed has the same electron configuration as the noble gas The symbol for the ion is The following Lewis diagram represents the valence electron configuration of a main-group element. -x This element is in group According to the octet rule, this element would be expected to form an ion with a charge of If X is in period 5 , the ion formed has the same electron configuration as the noble gas The symbol for the ion is The following Lewis diagram represents the valence electron configuration of a main-group element. :X: This element is in group According to the octet rule, this element would be expected to form an ion with a charge of If X is in period 2 , the ion formed has the same electron configuration as the noble gas The symbol for the ion is