The order of screening effect of electrons of s, p, d and f orbitals of a given shell of an atom on its outer electrons

s > p > d > f

The correct answer is option 2. s > p > d > f.

Let us delve into the concept of screening or shielding effect in atoms, which refers to how inner electrons reduce the effective nuclear charge experienced by outer electrons.

Screening Effect of Electrons in Different Orbitals:

s Orbitals:

Characteristics: Electrons in s orbitals are closer to the nucleus and have a spherical shape. They penetrate closer to the nucleus and experience a stronger attraction to the nucleus.

Screening Effect: Electrons in s orbitals provide the strongest screening effect because they shield the outer electrons effectively due to their proximity to the nucleus and their ability to occupy space closer to the nucleus.

p Orbitals:

Characteristics: Electrons in p orbitals are farther from the nucleus compared to s orbitals. They have a dumbbell shape and occupy regions that are further away from the nucleus.

Screening Effect: Electrons in p orbitals provide a moderate screening effect. While they do shield the nucleus to some extent, they are not as effective as s electrons due to their greater distance from the nucleus and their less centralized electron density.

d Orbitals:

Characteristics: Electrons in d orbitals are even further from the nucleus than p orbitals. They have complex shapes and occupy regions that extend farther out from the nucleus.

Screening Effect: Electrons in d orbitals provide a weaker screening effect compared to s and p electrons. Their diffuse nature and larger spatial extent mean they shield the nucleus less effectively than s and p electrons.

f Orbitals:

Characteristics: Electrons in f orbitals are the furthest from the nucleus among the commonly discussed orbitals in atoms. They have intricate, highly complex shapes and occupy regions that are extremely distant from the nucleus.

Screening Effect: Electrons in f orbitals provide the weakest screening effect. Their very large spatial extent and the fact that they are located far from the nucleus mean they shield the nuclear charge very poorly compared to s, p, and d electrons.

Order of Screening Effect:

Based on the characteristics described above, the order of screening effect from strongest to weakest is s > p > d > f

This means that:

s orbitals provide the strongest screening effect because they are closest to the nucleus and occupy space that directly shields the outer electrons from the nuclear charge.

p orbitals come next in screening effect, providing a moderate shielding effect due to their slightly greater distance from the nucleus compared to s orbitals.

d orbitals provide weaker shielding than s and p orbitals because they are further out and their electron density is more diffuse.

f orbitals provide the weakest shielding effect due to their very large spatial extent and their location far from the nucleus.

Conclusion:

Understanding the screening effect is crucial in explaining various atomic properties such as ionization energies, atomic sizes, and chemical reactivity. Electrons in different orbitals contribute differently to the shielding of outer electrons, affecting the overall behavior and properties of atoms and elements.