Shielding of the nuclear charge by the inner core of……A…….does not increase. Here, A refers to — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

When we move across a period across the second period, successive electrons are added to orbitals in the same principal quantum level and the shielding of the nuclear charge by the inner core of electrons does not PERIODIC PROPERTIES 37 increase very much to compensate for the increased attraction of the electron to the nucleus. Thus, across a period, increasing nuclear charge outweighs the shielding. Consequently the outermost electrons are held more and more tightly and the ionisation enthalpy increases across a period. As we go town a group, the outermost electron being increasingly farther