Which shells are called penultimate and prepenultimate shells?

Answer : Electrons are dispersed in the atom within the different shells of the atom around the nucleus. The outermost or the last shell of the nucleus is known as the valence shell.

Shells are generally circular orbits that contain rotating electrons around the nucleus within the shell.

The outermost shell is the valence shell where an element’s concluding electron exists. The shell closest to the valence shell is known as the penultimate shell, while the closest penultimate shell is called pre penultimate shell or anti-penultimate shell.

• The final shell of transition elements contains one or a couple of electrons. The penultimate shell comprises more than eight and up to eighteen electrons in the shell