|MadSci Network: Biochemistry|
Too many inconsistent answers. 1) Some claim that potassium alum, when applied to the skin via a solution of water etc, releases the exact same Al3+ ions, which is aluminum and so by dissociating in water it still delivers aluminum in the system. 2) It is said that some deodorant stones (or solutions) feature physically large potassium or ammonium alum molecules and are not absorbed into the skin/blood. Water has a molecular weight of 18. A potassium alum crystal molecule has a molecular weight of 474.38. A potassium or ammonium alum crystal molecule, in solution, is hydrated 24 times and consequently has a molecular weight of 654. It is impossible through natural means to get water to permeate the skin. Witness the large number of moisturizers available at the cosmetic counter and imagine how difficult it would be for a molecule that weighs 36.3 times as much as water to permeate the skin. I would like to find out which is accurate. Thank you. :)
Re: Is a potassium alum molecule too big to be absorbed into the (human) skin?
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