3. Where do you find the elements with the least atomic size, greatest electronegativity, and greatest ionization energy in the periodic table?

Atomic size - Francium 87

Electronegativity - Florine which is highest 4.0

Ionization energy - Helium,

so this all have the Highest size, so atom which is far from those have the smallest size, ionization energy and electronegativity.

Let me know if you have any question.