Science glossary film: Alkali metal

A highly reactive group of metals that make up group 1 in the periodic table. The alkali metals are lithium, sodium, potassium, rubidium, caesium, and francium. They are all soft, relatively low-density metals which react easily with air, and with water forming highly alkaline compounds. They become more reactive with increasing atomic number, and are often stored in oil to prevent combustion or corrosion.

The alkali metals are lithium, sodium, potassium, rubidium, caesium, and francium. They are all soft, relatively low-density metals which react easily with air, and with water forming highly alkaline compounds. They become more reactive with increasing atomic number, and are often stored in oil to prevent combustion or corrosion.