⚡ S-Block Elements – The Active Metals of the Periodic Table S-block elements are those in which the last electron enters the s-orbital of the outermost shell. They include Group 1 (Alkali metals) and Group 2 (Alkaline earth metals) of the periodic table. 🔹 Group 1 (Alkali Metals): Li, Na, K, Rb, Cs, Fr Highly reactive, soft metals Form strong bases like NaOH and KOH React vigorously with water 🔹 Group 2 (Alkaline Earth Metals): Be, Mg, Ca, Sr, Ba, Ra Less reactive than alkali metals Form oxid