Barium is an element in group 2 (the alkaline earth metals) of the periodic table, which indicates that it has 2 valence electrons. Additionally, being in period 6 suggests it is a heavier alkaline earth metal.
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It has 2 valence electrons and is highly reactive.
Alkaline earth metals, including barium, are not gases; they are solid metals at room temperature and are known for their reactivity, particularly with water and acids. They tend to react vigorously, although barium is less reactive than some other elements in the same group (like cesium or rubidium). Barium can react with water and air, thus it’s important to store it under oil or in an inert atmosphere to prevent oxidation.
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