Screening effect also known as shielding effect is when the electron in the outermost orbital faces inter electronic repulsion from the inner electrons, thus reducing the effective nucleur charge.
Na have higher shielding effect than Li *According to my chemistry book
Shielding.
Shielding.
The reduction in the force of attraction between the nucleus and outer most electron is known as shielding effect
in metals due to shielding effect ionization value is low
== == == == The screening effect, or shielding effect, is how electrons in the same atom interact with each other. In a single-electron atom (in isolation), the electron is only interacting with the proton; in a multielectron atom, the electrons are both interacting with the proton(s), but also with each other. While electrons are attracted to the protons in the nucleus, they are repelled by the other electrons. This electron-electron repulsion decreases the attractive force of the protons on the electrons.The shielding effect changes the effective nuclear charge -- effectively decreasing the true nuclear charge. This effect causes atoms to get smaller as you across a period (row) of the periodic table, as well as many other periodic trends observed in the periodic table.See the Web Links and Related Questions for more information about shielding and periodic trends.--------------------------------------------------------------------------- keep in mind that different orbitals have varying shielding effciencies depending on their shape and symmetry from greatest effect to least s>p>d>f and the effective nuclear charge can be estimated with good approx. by the Slater's Rule whereZ_eff=Z-S Z_eff= effective nuclear charge Z=nuclear charge S=screening (or shielding) factorthe screening factor is calculated by following the directions given at this websitehttp://intro.chem.okstate.edu/WorkshopFolder/SlaterRule.html
The shielding effect reduces the ionization energy and so makes cation formation easier.
When a period of elements are considered, the element in group 18 has the highest shielding effect.
•The shielding effect describes the decrease in attraction between an electron and the nucleus in any atom with more than one electron shell. •It is also referred to as the screening effect or atomic shielding. •Shielding electrons are the electrons in the energy levels between the nucleus and the valence electrons. They are called "shielding" electrons because they "shield" the valence electrons from the force of attraction exerted by the positive charge in the nucleus. Also, it has trends in the Periodic Table
Electron shielding is not a factor across a period because they all have the same number of electron shells! No further (extra) shells means that they are all affected by electron shielding equally.
this is because the effect of the increased nucleus i roughly balanced by the greater screening effect produced by adding to the penultimate shell