After filling the 4d-orbitals, an electron will enter in:

After filling up ‘4s’ orbital the electron enters:

a. In the sixth period, after filling of 6p orbitals, the next electron (i.e. 57th ) enters the 5d -orbital against aufbau principal and there after the filling of seven 4f -orbitals starts with cerium (Z = 71) . Explain this anomalous behaviour.

When the 3d orbital is complete, the new electron will enter the

When the 3d orbital is complete, the new electron will enter the

When the 3d orbital is complete, the new electron will enter the

When the 3d orbital is complete, the new electron will enter the

When the 3d orbital is complete, the new electron will enter the

When the 3d orbital is complete, the new electron will enter the

When 4f level of an atom is completely filled with electrons, the next electron will enter into which orbital?