The S-Block refers to a group of elements in the periodic table that includes the alkali metals and alkaline earth metals. These elements are found in the first two columns (Groups 1 and 2) and are characterized by having their outermost electrons in the s-orbital. Common examples include lithium, sodium, and calcium. They are known for being highly reactive, especially the alkali metals, which react vigorously with water. S-Block elements typically have low melting and boiling points compared to other metals. They are also good conductors of electricity and heat. The reactivity of these elements increases down the group, meaning that heavier elements like potassium and barium are more reactive than lighter ones. These properties make S-Block elements important in various chemical reactions and industrial applications.