Potassium is a highly reactive alkali metal that reacts vigorously with oxygen to form potassium oxide. To prevent potassium from reacting with oxygen, it must be stored in an oxygen-free environment. This can be achieved by storing potassium in a sealed container under an inert gas such as argon or nitrogen, or by coating it with a protective layer of oil or wax. Additionally, potassium should be kept away from sources of moisture, as water can react with potassium to form potassium hydroxide, which is a corrosive substance.