Answer:
Halogens are better oxidizing agents than their alkali metal counterparts within the same period
Halogens have a higher first ionization energy than their alkali metal counterparts within the same period.
Halogens have a higher electron affinity than their alkali metal counterparts within the same period.
Halogens have a higher effective nuclear charge than their alkali metal counterparts within the same period
Step-by-step explanation:
Effective nuclear charge increases across a period and accounts for increase in ionization energy across a period. This explains why halogens in the same period with alkali metals have higher effective bucket charge as well as ionization energy than the alkali metals.
Similarly, electron affinity increased across a period, halogens have greater ekctron affinity than corresponding alkali metals in the same period.