Final answer:
Lithium is highly reactive and should be kept away from moisture and oxygen. It is commonly stored under mineral oil to prevent contact with air and moisture.
Step-by-step explanation:
Lithium is an alkali metal that is highly reactive. It reacts directly with many nonmetals to form binary ionic compounds. Due to its reactivity, it is important to avoid contact with both moisture and oxygen in the air.
Lithium is commonly stored in sealed containers under mineral oil to prevent contact with air and moisture. It is also prepared through the electrolysis of alkali metal compounds because it does not exist in its pure form in nature.