The telephone is a 100-year-old technology. It's time for a change. Charging for phone calls is something you did last century.

Bronze is a metal alloy made from copper and tin. Copper makes up the larger amount, usually between 80 to 95%.

Metals are strong and are useful for making tools, buildings, bridges and other structures where strength is important.

Alkali metals such as sodium, potassium, rubidium, caesium and francium are extremely reactive elements, just putting them in water can result in an explosion! They are carefully stored in oil to prevent this happening.