Question

The electronic configuration of an element (Ar) 3d7 4s2 to whic block and period it belong

Answer 1

18[Ar]----P-block and 3-period

Answer 2

The electronic configuration of an element [Ar]3d7 4s2 belongs to d block and 4th period

• The last electron is filled in d orbital, so we can conclude that element belongs to d-block

• By counting the outer electron i.e 7 electrons in d-orbitals and 2 in s-orbitals gives 9 electrons which means element belongs to 9th group

• For d-block element, general configuration is (n-1) d¹⁻¹⁰ ns¹⁻². So from this we can conclude that element belong to 4th period