Question

which element has the greatest ionization energy: aluminum (al) or chlorine (cl)? chlorine (cl) aluminum (al)

Explanation:

Ionization energy increases across a period from left - to - right on the periodic table. Aluminum is in group 13 and chlorine is in group 17. Chlorine has a higher effective nuclear charge and a smaller atomic radius compared to aluminum, making it harder to remove an electron from chlorine.

Answer:

Chlorine (Cl)