(See sidebar on Davy in the calcium entry in Volume 1.) There are very few uses for potassium as a pure element.However, compounds of potassium have many important applications, the most important of which is as a fertilizer.But as soon as the element is formed, it reacts immediately with the water.

Then Davy thought of another way to separate potash and soda ash into their elements. Instead, he melted a sample of potash and a sample of soda ash.

Then he passed an electric current through the molten (melted) substances.

Common household lye (such as Drano) is a typical alkali.

The chemical name for potash is potassium carbonate (K ).

The first method that Davy tried was to pass an electric current through a water solution of one compound or the other. What Davy did not know was how active the elements potassium and sodium are.

Both elements are freed when an electric current is passed through a water solution of potash or soda ash.

By the late 1700s, chemists were reasonably sure that both potash and soda ash contained elements they had never seen.

They tried to think of ways to break these compounds down into their elements.

The two materials looked and acted very much alike.