Friday, 29 January 2010

Dilutions and Avogadro

The critics of homeopathy are always going on about Avogadro's number, which is 6.022 x 10 to the power 23. I wonder how many of them actually understand it.

So here is my attempt at a very simple explanation of what it is all about. Amedeo Avogadro in 1811 hypothesised that 'Equal volumes of ideal or perfect gases, at the same temperature and pressure, contain the same number of particles, or molecules'. What he meant by that was that the same volume of a gas, whether it is hydrogen, nitrogen, oxygen or anything else, will contain the same number of molecules if the temperatures and pressures are the same. This is Avogadro's Law.

Long after he died other scientists recognised what an important contribution he had made and the Avogadro Constant is named after him but the concept of the mole to which it refers was not known in his lifetime.

Now for a basic chemistry lesson, so pay attention.

One mole of a substance is the molecular weight in grams of that substance. Hydrogen has a molecular weight of 1, so 1 g is 1 mole of hydrogen. Carbon has a molecular weight of 12 and so 12g of carbon is 1 mole.
Going back a bit Avogadro said 'Equal volumes of ideal or perfect gases, at the same temperature and pressure, contain the same number of particles, or molecules'.

So.. One mole of a substance will always contain the same number of elemental particles (usually atoms or molecules) and that number (according to many clever scientists) will be 6.022 x 10 to the power 23, this can also be written as 602 200 000 000 000 000 000 000 particles, which is an awful lot of particles.

So 1g of hydrogen and 12g of carbon are both one mole and will both contain 602 200 000 000 000 000 000 000 particles.

Are you still with me? 

The problem sceptics have is that homeopathic remedies are very diluted. A 12c homepathic remedy is technically a dilution of 1 x 10 to the power 24, and so that means 1 part in 1 000 000 000 000 000 000 000 000 and that is more dilute than Avogadro's number which means any remedy 12c or more dilute should contain none of the original particles. Many homeopaths use remedies in a variety of strengths from tinctures to extremely diluted remedies. What the sceptics always seem to forget, or ignore, is that homeopathic remedies are not just diluted, they are also shaken vigorously between each dilution which is a process known as succussion. There are several studies that show the succussion process means the solutions are very different from ones which are just diluted and not shaken.

There is a whole branch of science looking at the peculiar properties of ultra diluted solutions and there is absolutely no doubt that there are many scientific peer reviewed published papers which demonstrate that a substance which has been diluted and shaken is still measurable way beyond the point that it should be. There have been positive experiments using a whole host of different analytical techniques and the laws of physics and chemistry cannot currently explain why these ultra diluted and shaken substances can still be measured.

The International Journal of High Dilution Research is the first full free open-access electronic journal specialising in the multidisciplinary field of High Dilution (HD) research.  Lots of articles on analytical research, plant, veterinary, pharmacological studies as well as literature reviews and much more.

This has been known about for a very long time and we still do not fully understand the processes which make these dilutions active. The first published paper on the strangeness of highly diluted and shaken solutions was by Bertrand Gabriel 'The Extraordinary Sensitiveness of Aspergillus niger to Manganese' Comptes Rendus Académie des Sciences published in 1912!

There are many theories like nano particles, local coherent quantum domains, memory of water or something completely different. This is not just of interest to homeopaths, many chemists, physicists and materials scientists are doing research in this area.

One of the key papers on this subject is by the physicist Dr Louis Rey, he used very diluted and shaken solutions of lithium chloride and sodium chloride and then analysed them using a technique called thermoluminescence. It showed conclusively that very dilute solutions were measurable when they were diluted beyond the point there should be any particles present.

There is much more evidence from analytical chemistry, plant and biological systems too. Have a look at this section on dilutions from the excellent website Extraordinary Medicine.

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