My source wrote:
> He {glen} is not talking about the precipitation of CaCO3 from
> solution. He is talking about the formation of CaCO3. There is a big
> difference here. In this case, the source of carbonate must be from carbonic
> acid which comes from CO2 dissolved in water and a source of calcium.
> Those calculations I
> made are correct. The amount of heat liberated during precipitation is not
> going to be any where near what he says. That kind of heat is liberated only
> in vigorous reactions.
> Ask him if he understands that precipitation is controlled by the
> solubility of a salt, even CaCO3 which is the salt of carbonic acid (that's
> where the CO3 comes from) and calcium ion. If he does understand this, then
> show him that the amount of heat that is going to be liberated must follow
> the formula I gave you. I'll show it again below.
>
> Gibbs free energy of a reaction = -RTlnK
>
> where R = the gas constant, T = degrees Kelvin, lnK is the natural log of K,
> K is the solubility product. See if he understands that precipitation does
> depend on the solubility.
Ok. Your turn.
-- Allen & Diane RoyCreationary Geology Tours of Grand Canyonhttp://www.tagnet.org/anotherviewpoint/Daniel Prophecy Studieshttp://www.tagnet.org/anotherviewpoint/Daniel/