Fluorine is the lightest halogen element and the most reactive chemical element.
Because of its great propensity to attract electrons and the small size of its atoms, it has high chemical activity.
Halogen with the highest level of reactivity:
Fluorine has the shortest atomic size of all the halogens. As a result, the nuclear attraction on the furthest electrons is greatest.
Among the halogens, fluorine is the most reactive.
Group seven's most reactive element, fluorine, is significantly more reactive than chlorine. The outer shell of fluorine is closer to the nucleus and has fewer filled spaces.