Re: Organic Gel

JRS: In article <fLyxe.1221$qt3.1196@xxxxxxxxxxxxxxxxxxxx>, dated Sat,
2 Jul 2005 15:52:43, seen in news:uk.rec.scouting, John McMahon
<johnDOTmcHYPHENmahon@xxxxxxxxxxxx> posted :


>Trying to find a source of Calcium Acetate is difficult, but a little school
>boy chemistry suggests that using 2 parts Acetic Acid (vinegar) and 1 part
>Calcium Carbonate (chalk!) should produce the required precipitate.
>Calcium carbonate = CaCO3
>Acetic acid = CH3CO2H
>
>2 CH3COOH + CaCO3 = H2O + CO2 + Ca(CH3COO)2
>
>Obviously Carbon Dioxide as a by-product means that you should do this is a
>well ventilated area.


Chalk is approximately 100% CaCO3.
Vinegar (vin aigré) is about 5% CH3COOH.

One mole of CaCO3 weighs 40 + 12 + 3*16 = 100
Two moles of C2H4O2 weigh 2 * ( 2*12 * 4*1 + 2*16 ) = 120

Vinegar has a specific gravity of about 1; chalk probably more like 3 or
4; so the volume of vinegar required will be something like 100 times
that of the chalk.

A litre of air weighs 6 grams, and holds about 3 mg of CO2. An ordinary
room is say 30 m^3, 30000 L, so holds 100 g of CO2. But several times
that amount will not be hazardous; and the ventilation required to deal
with the smell of fizzing vinegar should deal amply with the CO2.

Check all those figures.

I suspect Calcium Acetate is very soluble in water; you'll need to be
able to dry it.


How much CO2 is produced by the average Troop breathing during a
meeting?

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Relevant Pages

  • Re: Organic Gel
    ... >>>Calcium Carbonate (chalk!) should produce the required precipitate. ... >> with the smell of fizzing vinegar should deal amply with the CO2. ... >chalk to produce 6.58g calcium acetate and 1.83g carbon dioxide. ...
    (uk.rec.scouting)
  • Re: Organic Gel
    ... >>Calcium Carbonate (chalk!) should produce the required precipitate. ... > with the smell of fizzing vinegar should deal amply with the CO2. ... chalk to produce 6.58g calcium acetate and 1.83g carbon dioxide. ...
    (uk.rec.scouting)
  • Re: Pitmans Miller Time
    ... The formation of the chalk layers in the ... |>England and the southern North Sea basin are? ... assume sufficient light levels the entire depth of the water column) ... | So to produce 1000m of chalk we need to extract the Calcium Carbonate ...
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  • Re: Pitmans Miller Time
    ... |>>> redeposited chalk from adjacent shallower areas. ... |> You can only increase the Calcium Carbonate concentration of sea water ... water does not have an infinite capacity for the dissolution ... | they cut out the light and *reduce* the depth of the photic zone. ...
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  • Re: Pitmans Miller Time
    ... produced very thick chalk layers in very short order. ... How thick do you think that the chalk beds of southern and eastern England and the southern North Sea basin are? ... Calcium Carbonate is about 0.1% by mass of sea water. ...
    (talk.origins)