Potash What is it? What does it do?

POTASH

This can mean one of two things. It either refers to ashes left over after a wood fire or potassium compounds. In this case we are referring to postassium. Potassium is a metal. The metal is the seventh most abundant and makes up about 2.4% by weight of the earth's crust (wow!). Potassium is an essential constituent (fancy words for important) for plant growth and it is found in most soils. It is also a necessary element in the human diet. Potassium is never found free in nature, but is obtained by electrolysis of the chloride or hydroxide, much in the same manner as prepared by Davy. It is one of the most reactive and electropositive of metals and, except for lithium, it is the lightest known metal. It is soft, easily cut with a knife, and is silvery in appearance immediately after a fresh surface is exposed. It oxidises very rapidly in air and must be stored under argon or under a suitable mineral oil. As with other metals of the alkali group, it decomposes (rots, breaks down) in water with the evolution of hydrogen. It catches fire spontaneously (without lighting) on water. Potassium and its salts impart a lilac colour to flames.