The Order of the Elements

The explosive story of chemistry is the story of the building blocks that make up our entire world - the elements. From fiery phosphorus to the pure untarnished lustre of gold and the dazzle of violent, violet potassium, everything is made of elements - the earth we walk on, the air we breathe, even us. Yet for centuries this world was largely unknown, and completely misunderstood.

In this three-part series, professor of theoretical physics Jim Al-Khalili traces the extraordinary story of how the elements were discovered and mapped. He follows in the footsteps of the pioneers who cracked their secrets and created a new science, propelling us into the modern age.

In part two, Professor Al-Khalili looks at the 19th-century chemists who struggled to impose an order on the apparently random world of the elements. From working out how many there were to discovering their unique relationships with each other, the early scientists' bid to decode the hidden order of the elements was driven by false starts and bitter disputes. But ultimately the quest would lead to one of chemistry's most beautiful intellectual creations - the periodic table.