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( or Order from Chaos?) These days we are always hearing about 'organic' food. So what do the terms organic and inorganic really mean? At present if one reads about organic foods, what is usually meant is that they are simply grown in an environment which is free from man-made chemical pesticides and herbicides, and that the producer has used only natural fertilizers and herbal pesticides - like certain species of flowers - as herbicides, and animal manures. But they certainly don't talk about 'inorganic' vegetables! When people were investigating the properties of matter hundreds of years ago, they first made two divisions. Things like trees, animals, herbs and so on, which had once lived and came from natural sources began to be called 'organic'. Things like minerals which came from the ground, like gold, silver, gemstones, sulphur, clays, metal ores and so on, were called 'inorganic' because they were not produced by life. A nice natural division? No. How do you place mineral oil? Then, as the study grew more selective, they found animals breathed out carbon dioxide gas, which could form salts called carbonates. But it was found that carbon dioxide could be made from materials which had never been associated with life. If you burnt certain trees and shrubs you could obtain an alkaline substance called potash - which could also be found underground in certain dry countries. If you dug in certain cliffs you could get limestone - which was composed of sea animal shells. Organic? Inorganic? Hmmm. The scientists decided that organic chemistry was the chemistry of compounds containing a carbon atom. Urea, which was used as a fertilizer and was derived only from animal products, and contains carbon atoms was therefore termed organic. But a German chemist spoilt that idea by making urea from materials which had never had anything to do with life or life processes. So urea could be organic or inorganic. More hmm? Scientists are notorious for their determination to place everything they come across in pigeon holes; they have the urge to categorize everything. So it was decided to make organic chemistry the chemistry of any substance with two or more carbon atoms. And that's how it stayed for some time. Until about 50 years ago laboratories such as those in Universities and those which had very big collections of chemicals had two separate store rooms - the Organic stores and the Inorganic stores. But modern chemists began to feel awkward about this division; it seemed a bit vague. So they don't feel the need to talk about organic and inorganic materials. They no longer feel that to be necessary; they have one chemical store, and instead of categorizing as they once used to, chemicals are most easily found when stored in purely alphabetical order. It is then that chemists hit another snag. Alcohol is also called ethanol, so do you put it among the A's or the E's? Well, its original name was Arabic 'al coul'. The old name became lost and it was called alcohol for hundreds of years. There are a very great many chemicals no longer called by their original name. Take mercury; that was once called by the Latin 'Hydrargyrum', and is still given the symbol Hg. Then it became 'quicksilver', and it is only fairly recently it became mercury. And so we can go on: 'spirits of hartshorn' - ammonia. 'Muriatic acid' next became 'spirits of salt' then hydrochloric acid. 'Spirits of nitre' - nitric acid. Then there's things like 'Decoction of Willow Bark' which became eventually acetyl salicylic acid - which you know well as aspirin, (it is now completely synthesized). Like I said, one could go on and on ... so around a hundred years ago the chemists got together and came up with names for chemicals based on what the single molecule was like. Thus ethanol derived from a gas called ethylene, renamed ethane, and the 'ol' bit from the fact the ethanol molecule has a hydroxyl (OH) group sticking out. So now you know why you won't find a dye called 'bismark brown' under B in the chemical store. You would have to learn some chemistry and look under T for 'tetramethyl diamino diphenyl methane'. Or check it out in a thick book called “The Handbook of Physics and Chemistry” which gets bigger every year, so has to be frequently republished with all the new compounds included - what a job! But the chemical will be listed under its proper scientific name, and everyone is supposed to use that. It's supposed to be international, but what can you do with Germans who insist on calling 'sodium sulphate' 'natrium schwefelsaures'? Did I say 'Order from Chaos'? and further: G'day; Now I've come all over academic (Shame, shame!!) The word ORGANIC has had it's original meaning considerably changed in the last half century. If applied to a material it used to mean that the material was the product of some life process, and the word INORGANIC was applied to anything that was not the result of a life process. Thus all vegetables, plants and animals are organic in origin. Thus to talk about , say, 'organic lettuces' is nonsense - or course they are organic. Inorganic lettuces don't exist. So if you take a lettuce seed and grow it in a fertilizer made of minerals (nitrates, sulphates, iron, cobalt, selenium etc) that lettuce is still organic. So it was grown with inorganic fertilizers instead of life produced ones (like manure, compost, etc), but it is still organic. Lets consider a material used by jewellers; 'Liver of Sulphur' (potassium poly sulphide) is inorganic; made from potassium and sulphur. 'Lime sulphur' (calcium poly sulphide is made by heating lime with sulphur. So it is an inorganic blackening agent for silver and copper. You want an organic agent? Well, stew your silver or copper with onions, or garlic, and the organically produced sulphur compounds in these once-living plants will blacken the metals. And by the way, whilst I'm being academic, the silver or copper is not oxidized to blacken it; the metals are sulphided!! OK, so what about limestone, calcium carbonate? Bit confusing here. Most limestone is the product of marine animals which once lived, BUT - and here's the confusion. Before life formed on this earth, there was calcium carbonate, and some of it still exists. Well, organic or inorganic? So you see things get difficult if one tries to be too clever! These days chemists try not to mention the two word Cheers for now, John Burgess Mapua, Nelson NZ |
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