Chemistry · Chemical Bonding

Across a period, the number of shells remains the same. The shielding effect is between the outer electron and the nucleus, hence, the more the shells the more the shielding effect. As the number of shells remains the same, the shielding effect remains the same.

Screening or shielding effect increases in a group as shells increases from top to bottom but in a period it decreases from left to right because of increase in atomic number and no change in shells. Hence in a period, it does not increase whereas in a group increases

Across a period, the number of shells remains the same. The shielding effect is between the outer electron and the nucleus, hence, the more the shells the more the shielding effect. As the number of shells remains the same, the shielding effect remains the same.

Electron shielding describes the ability of an atom's inner electrons to shield its positively-charged nucleus from its valence electrons. When moving to the right of a period, the number of electrons increases and the strength of shielding increases.

Across a period, the number of shells remains the same. The shielding effect is between the outer electron and the nucleus, hence, the more the shells the more the shielding effect. As the number of shells remains the same, the shielding effect remains the same.