This element is the lightest alkali metal and it is very reactive. This metal is used for the production of dry cells and storage batteries (for cell phones, car batteries, etc.). The carbonate of this metal is used for the treatment of some mental decease.
This element is a transition metal used in large amounts by the electrical industry in the form of wire. This metal is the second-best in the electrical conductance. Because this element resists corrosion in air, moisture and seawater, it has been widely used in coins.
This element is classified as an actinide and it is solid at room temperature. It is a synthetic transuranic element and can be produced in kilogram quantities. It is used in smoke detectors and as a portable source of gamma rays.