Although it is a solid at room temperature, the metallic element sodium is not found in its pure state naturally. A highly reactive element, sodium is found in the Earths crust and oceans combined with other elements as a compound.
The sixth most abundant element found in the Earths crust, sodium (Na) very easily combines with elements from the halogen family and forms ionic salts. The most common of these salts is the one formed when sodium combines with chloride to form what we know as table salt (NaCl). Because sodium has only one electron in its outermost electron shell, it will readily give up that electron to bond with a highly electronegative element.