Question

Explaine why 4s electrons are removed before 3d electrons in transition metals

Answer 1

Electrons are filled in the orbitals with lower energy first. As 4s orbitals have a lower energy than 3d orbitals, electrons are first filled in the 4s orbital and then in the 3d orbital. When electrons are ionised, they are always removed from the outermost or valence shell.

Answer 2

Electrons are filled in the orbitals with lower energy first. As 4s orbitals have a lower energy than 3d orbitals, electronsare first filled in the 4s orbital and then in the 3d orbital.