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Originally Posted by Michaelangelica
I don't understand the chemistry of salt (I have no understanding or training in chemistry -but try). I can't understand why you can't just add some chemical to water and all the salt molecules just fall out. That's why I was fascinated by my pool chlorinator (new house; first pool-saltwater).
How come this technology is not used to make drinkable chlorinated drinking water?
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Well! Michael, perhaps I can help. (I do have a hell lot of training in chemistry), So I must try to put your doubts in place
First of all, there really is no chemistry of salt. Chemists study a class of substances called
salts, Sodium chloride is a kind of salt, an ionic compound that is made up of a lattice of sodium and chloride ions.
Because it is ionic, and made up of sodium and chloride ions, it is one of the most soluble salts in water. That means lots and lots of salt can get dissolved in water. Because, it is made up of sodium and chloride ions, and most of the salts of these ions are very soluble in water, it cannot be easily precipitated. That is, it cannot be removed from water by adding another substance. In any case when we add some salt to precipitate another salt, a bit of the other substance is left behind in the water. Unfortunately, most other salts are not as benign to the human body as sodium chloride. Sodium chloride is so benign because it is present in limited quantity in all our body cells.
Salt can indeed be removed from water, by a process called reverse osmosis. There are a certain kind of membranes that can filter off the sodium and chloride ions. But, reverse osmosis is not a low cost solution, that's why it is not very economical.
I have not hyperlinked many technical words, because I believe that intelligent curious people should not be spoon fed all the info. Go to
wiki or any other search engine and you will find enough information about them.
