Q.Define:
a. Ionic radius
b. Electronegativity

Step 1. Define ionic radius. The effective radius of a cation or anion, estimated by measuring the distances between neighbouring oppositely-charged ions packed together in an ionic crystal (section 7.5.2.2) — analogous to how atomic radius is estimated from internuclear distances for neutral atoms.

Step 2. Define electronegativity. The relative ability of an atom, when it is covalently bonded to another atom, to attract the shared pair of bonding electrons toward itself; it is expressed on numerical scales such as the Pauling scale, on which fluorine (the most electronegative element) is assigned the reference value 4.0 (section 7.5.2.5). …

Stating the chapter's own definitions of ionic radius (section 7.5.2.2) and e …

• Defining ionic radius the same way as covalent/atomic radius (bond length ÷ 2) instead of specifically citing inter-ionic distances in a crystal. …