Alkali metals are a group of elements found in Group 1 of the periodic table. They include lithium, sodium, potassium, rubidium, cesium, and francium. These metals are known for being highly reactive, especially with water, and they tend to lose one electron easily, forming positive ions. This reactivity increases as you move down the group. Due to their reactivity, alkali metals are not found in their pure form in nature; instead, they are usually found in compounds. For example, sodium is commonly found in table salt, or sodium chloride. Their unique properties make them important in various applications, including batteries and chemical reactions.