Question
Can an element with atomic number 126, if discovered, be accommodated in the present Un set up of the long form of periodic table?
✓
Answer
No, the maximum number of elements which can be accommodated in the present set up of the long form of the periodic table is 118. Thereafter, filling of 8s-orbital shell begin which will accommodate only two electrons. After 8s-orbitals, the filling of 5g-orbitals will begin. Since we do not have any provision for g-block elements in the present set up of the long form of periodic table, therefore, an element with atomic number 126, if discovered, cannot be accommodated in the present set up of the long form of periodic table.
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