Answer to Question #186349 in General Chemistry for wwws

Question

Define shielding effect and describe its trends in periodic table wit suitable examples

Answer 1

This effect, called the shielding effect, describes the decrease in attraction between an electron and the nucleus in any atom with more than one electron shell. The more electron shells there are, the greater the shielding effect experienced by the outermost electrons. . As a result, atoms will be larger.

The more shielding electrons you have, the lower the ENC, so the less force there is holding onto the outer shell electrons.Therefore when you move down the left-hand-side of the periodic table, atoms become more reactive - more liable to lost electrons.