Question

Among the elements of the third period Na to Ar pick out the element:
(a) with highest first ionisation enthalpy
(b) with largest atomic radius
(c) that is most reactive non-metal
(d) that is most reactive metal

Answer 1

(a). Sodium (Na)
(b). Argon (Ar)
(c). Phosphorus (P)
(d). Sodium (Na)