An element’s chemical activity is defined as its stability relative to the elements surrounding it on the periodic table. Chemical activity is also related to electronegativity. Elements that are highly electronegative are highly reactive, while elements that have low electronegativity are less reactive.
Fluorine is the most electronegative element on the periodic table and thus is the most chemically reactive. Elements that are near fluorine also have high electronegativity values and are also highly chemically active. In general, the least chemically active elements are the transition metals, including copper, silver and gold. These elements have low electronegativity and low reactivity.