The electronic configuration of an element ‘X’ is 2, 8, 6. To which group and period of the modern periodic table does ‘X’ belong. State its valency and justify your answer in each case.
Electronic configuration of X = 2, 8, 6
Group number = 10 + Number of electrons in outermost shell = 10 + 6 = 16
Since there are 3 shells, it belongs to the 3rd period.
X has a tendency to accept 2 electrons in order to attain noble gas configuration i.e. 2,8,8. Therefore, the valency of X is 2.