Page 5 - Curriculum Visions Dynamic Book

by boiling and then reducing to a powder.This gave rise to the term ‘pot ash’, literally the ash left in the pot.The potash was then mixed with animal fat to make the soap.
One of the main
applications of potassium
salts is as fertilisers, often
as nitrate and sulphate.
Potassium nitrate and
potassium chlorate go
into fireworks. Potassium permanganate is an oxidising
agent and an antiseptic, and
was used to dress wounds. Potassium replaces sodium
in low-sodium salt products
for people with high blood pressure. Potassium phosphate is a common ingredient in detergents.
Geology
Potassium makes up about 1.5% by weight of the Earth’s crust. Many potassium salts are evaporite deposits, produced by the drying out of salt water lakes and lagoons. Potassium is much rarer in sea water than sodium is.
The dominant mineral in evaporite deposits is potassium chloride (KCl). In many other minerals potassium plays
an important part in determining structure and colour. Potassium
is, for example, found in feldspars, an important
mineral in igneous rocks. Carnallite is a
potassium-rich metal. Potassium salts are
mined at Stassfurt, Germany, and in
the United States.
 Potassium metal reacts violently with water, producing flames and an alkaline solution of potassium hydroxide.
 Common minerals such as feldspar contain potassium.
5
Biology
Potassium is essential for plant growth and animal development. It is found naturally in many soils and is one of the main elements applied in fertilisers.
Potassium plays a vital role in controlling the movement of fluids inside cells and is essential to the working of nerves and the heart.There is no need to add potassium to normal diets because it is in most foods.