Question

The electronic configuration of three elements are given below:
x 2
y 2,6
z 2,8,2
1) Which elements belongs to the second period of the periodic table?
2) Which elements belong to the eighteenth group of the periodic table?

Answer 1

a. z : 2,8,2 i.e. magnesium
b. x: 2 i.e. helium

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