What is the shielding effect?

The shielding effect is the phenomenon due to which the outer electrons of atoms are shielded or partially blocked from the full charge of the nucleus by the inner electrons. This effect occurs in multi-electron atoms, where the outermost electrons experience less attraction from the nucleus due to the shielding effect from the inner electrons.

The shielding effect is caused by the repulsion between electrons that occupy the same orbitals. This repulsion causes electrons in the inner shells to screen, or shield, the outer electrons from the full attraction of the nucleus. The shielding effect is also influenced by the distance between the electrons and the nucleus, as electrons that are closer to the nucleus have a stronger attraction and shielding effect.

The shielding effect affects the atomic radius, ionization energy, and electronegativity of atoms. Elements with more electron shells and more inner electrons have a larger shielding effect, resulting in larger atomic radii and lower electronegativity. On the other hand, elements with fewer electron shells and fewer inner electrons have a smaller shielding effect, resulting in smaller atomic radii and higher electronegativity.

Overall, the shielding effect plays a crucial role in the behavior and properties of atoms and elements.