a chemist made the table below to record some atomic properties of four elements. based on the information in the table, which conclusion about the chemical reactivity of these elements is valid?

Answer is: Fluorine is the most reactive because it has 7 electrons in the outer shell.
Number of electrons in outer shell determines atom reactivity, not number of protons and neutrons.
Electron configuration of fluorine: ₉F 1s² 2s² 2p⁵.
Electron configuration of neon: ₁₀N 1s² 2s² 2p⁶.
Fluorine tends to have eight electrons in outer shell like neon (noble gas) and gains one electron in chemical reaction.