Question

The screening effect of $s$ orbital electron is :
A. Greater than $p$ but lesser than${\rm{d}}$ and $f$ electrons
B. Less than$p$, $d$ and$f$ electrons
C. Greater than $p$, $d$ and $f$ electrons
D. is equal to $p$,$d$ and $f$ electrons

Answer 1

The screening effect or the shielding effect is the phenomenon which arises in such atoms which have electron shells or say have more electrons

Complete step by step answer:
Screening effect is also known as shielding effect. As we know the electrons are negatively charged and the nucleus is positively charged due to the presence of positively charged particles called protons in it. Due to the presence of opposite charges, the electrons in the outermost shell or valence shell gets attracted towards the nucleus. But on the other hand the electrons in the outermost shell and the inner shells bear the similar charge i.e. negative charge. That is why there is a force of repulsion between them. As a result, the force of attraction between the valence electrons and the nucleus gets decreased. This effect is termed as the screening effect or the shielding effect.
The screening effect or the shielding effect is totally dependent on the electron density of the orbital. Greater the electron density leads to the greater shielding effect. Since $s$ orbital is nearest to the nucleus and is spherical in shape that means it must have more electron density. Whereas the p and d orbitals are dumb-bell and double dumb-bell shaped as well as farther from the nucleus, so will have lesser electron density than s orbital. $f$orbital is the farthest orbital from the nucleus as well as is diffused in shape. So the electron density will be least in case of $f$ orbital. So the order of screening effect of the orbitals will be;
$s > p > d > f$
Thus, the correct option is C
Note:
Thus, screening effect can be defined as the reduction in the effective force of attraction between the nucleus and the valence electrons due to the electrons in the inner shells.