Changing the way you learn

Question	Answer
Soft Water	Water containing no dissolved calcium and/or magnesium salts, so it easily forms a later with soap
Hard Water	Water in which it is difficult to form a lather with soap Water containing calcium and/or magnesium ions which react with soap to form scum
Scum	The precipitate formed when soap reacts with calcium or magnesium ions in hard water
Soapless Detergents	A cleaning agent that does not produce scum when used with hard water
Scale (limescale)	The insoluble substance formed when temporary hard water is boiled
Temporary Hard Water	Hard water which is softened when it is boiled
Permanent Hard Water	Hard water whose magnesium and/or calcium ions are not removed when the water is boiled, thus remaining hard
Ion-Exchange Column	A water softener which works by replacing calcium and magnesium ions with sodium or hydrogen ions, removing the hardness

Chapter 2 - Water

	Created by rosetinley about 11 years ago