Periodic Trends in Physical Properties

Many physical properties of elements — melting point, boiling point, density among others — show clear periodicity. This section focuses on five specific physical properties that are examined here in detail and that recur throughout the rest of the chapter's worked problems: atomic radius, ionic radius, ionization enthalpy, electron gain enthalpy, and electronegativity. Each is defined precisely, then explained in terms of the effective-nuclear-charge and screening-effect framework introduced …