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On Sunday 08 May 2011 23:02:16 Alan McKinnon wrote: |
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> Apparently, though unproven, at 00:14 on Monday 09 May 2011, john did opine |
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> |
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> thusly: |
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> > Great widgets. Not sure what a Molar Mass Calculator does? Perhaps |
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> > weighs your teeth?? |
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> : |
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> :-) |
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> |
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> "Molar" as in the adjective describing "mole" as in "quantity of matter" as |
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> in "some gigantic number of identical atoms (or maybe it's molecules)". |
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> It's a very useful measure of "some quantity of stuff". |
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> |
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> IIRC the gigantic number is Avogadro's number, on the order of 10^124. So |
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> one mole of hydrogen would be the amount of hydrogen containing that |
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> number of hydrogen atoms (or maybe it's molecules. Whatever.) |
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Here's a quotation from http://en.wikipedia.org/wiki/Mole_%28unit%29: |
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"The mole is defined as the amount of substance that contains as many elementary |
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entities (e.g., atoms, molecules, ions, electrons) as there are atoms in 12 g of |
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the isotope carbon-12 (12C).[1] Thus, by definition, one mole of pure 12C has a |
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mass of exactly 12 g." (I don't know how those super- and subscript numbers will |
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appear in e-mail.) |
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You just knew you were setting yourself up, didn't you? :) |
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-- |
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Rgds |
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Peter |
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