Olio di semi, olio d’oliva, burro, strutto: per la Chimica, sono tutti acidi. Acidi grassi, per la precisione: la definizione corretta è questa. Non c’è da impressionarsi: per un chimico, la parola “acido” ha un significato ben preciso, diverso dal significato che ha nelle conversazioni quotidiane; ma per spiegare bene cos’è un acido servirebbe un corso di chimica, non mi sembra il caso di parlarne qui.
Nel parlare comune, al di fuori della chimica, “acido” è qualcosa di corrosivo, sia in senso letterale che come metafora: ma in chimica non è obbligatorio che un acido sia corrosivo, esistono gli “acidi forti” ma anche gli “acidi deboli” - We know all the butter and oil, does not seem to explain the case to it right now. And most importantly, there are corrosive substances that are not classified as acids: caustic soda, for example, is not an acid but it is very dangerous.
fatty acids, the oil and butter, are part of organic chemistry, that is connected to life: in fact they are all plant or animal origin. Organic chemistry is the chemistry of carbon , an element in the periodic system has the symbol C (CARBON) and atomic number 6.
carbon in nature is presented both as a gas or mineral (carbon dioxide, coal, diamonds ...), ie inorganic form in which it is closely related to life, that is organic.
Even this is something almost impossible to explain unless you seriously study the chemistry, but the organic carbon (one of which we are made, animals, plants) has the ability to bind its atoms in long chains, linked its almost like pearl necklaces. This ability to form chains of atoms, even very complex in nature, has only the carbon: it is one of the mysteries of life, one of those that do not come we are still in charge. And it is a ring of carbon atoms that we must think, then, for the fatty acids, the oil and the burro.Anche DNA, "acid deoxyribonucleic acid, is formed by a long chain of carbon atoms, variously combined.
acids in organic chemistry, ending all their chemical formula with a characteristic group,-COOH . The difference lies in the number of atoms along the chain: for simplicity, can you imagine the-COOH group of atoms (these are symbols of oxygen and hydrogen linked to carbon atoms) as a tag attached to the necklace. The first series of organic acids (but we are not fatty acids) is formic acid, with a single carbon atom: it is precisely that of the ants, the name comes from there. Acid pure formic acid (which is obtained by chemical synthesis, and not the ants) is a colorless, pungent smell. In second place is acetic acid, and just smell the vinegar to recognize its presence, a very characteristic odor. The complete table of organic acids I put below, the divide in two for convenience, because it is very long (by clicking the image you can read all).
The term "fatty acids" (in English, "fatty acids") is commonly given from 10-12 carbon atoms on , and is not a proper scientific name but is very common in everyday practice. Although acetic acid and formic acid are two names in common use, we use a lot and have a long history behind them, the actual chemical names are much more complicated but very useful if you need to go back to the molecular structure.
There are also very curious names, the list of organic acids, for example, acid and acid goats goats. Having handled acid goats (which is another clear, colorless liquid) can assure you that it smells very strong and very particular - in short, really stinks like a goat, and is one of the components of "dirty" that we take off for washing the back. Almost all
these organic acids are used in the production of raw materials for industry, including acid goats, but the real point of interest are fatty acids, which are made with detergents, soaps, shampoos, beauty creams.
Oleic acid is the main component of olive oil, has a complex structure, no longer a linear chain, another chain of atoms, but more elaborate. One of the last table of this organic acid is salicylic acid : that, with a slight modification (acetylation) becomes acetyl salicylic acid, namely aspirin. As the name implies, is originally from the bark of willow trees, and is a pure white powder.
It also said that the name of each fatty acid does not mean that only extracted from the plant or the seed: linoleic acid is not present only in linen but also in animal fats, and the same holds true for palmitic acid, myristic, lauric, and I am - not being thin - I certainly harbor him.
It 'still a complex discourse, which can be addressed with precision only by studying the chemistry, but it is important to know the products with which we deal every day, and I know that for many (especially those who have high school Classic), these things are totally unknown and mysterious, but rather with a bit 'of good will can understand. I often meet people who know nothing at all of the products they are purchasing and using, not trust advertising and if they buy cakes and biscuits can not even read the ingredients list (which is compulsory by law). The school unfortunately does not explain almost anything, just my diploma in chemical to make the expert (which are not, either). So if anyone has come up at the bottom of my writing and has produced something, I heartily thank him, and at least for now I can quit happy.
PS: The table is from my old school book, kept in a safe (well, almost). The first column is the name commonly used, the chemical formula in the second, third and fourth in the melting point and boiling point, then the specific gravity (Density: all oils and fats float on the water), and finally the solubility in water which is good for formic acid and acetic acid, then gradually becomes more difficult: oil and water, you know, not mix - at least to make an emulsion, but this would open a whole other subject.
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