
hredzak
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Absolutely, thank you Tom! 9-9-09Run.rea
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Hi Tom, Okay, I think I got it - but for the mineral view I want to make sure I'm interpreting these predictions right. So basically for the barium minerals, witherite and barite will both form in the solution in small amounts (up to 10-4M), then where these curves level off it is precipitaing out of solution at that point? Thank you!
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One more question, how can I tell what will be precipitated? (Can I tell what will be precipitated?) Essentially I want to know if it will be BaSO4 and see how much.
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Also - I guess I need Ba++ concentration in my starting solution?
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Under simple reactant - aqueous I only have BaCl+. Under minerals I have BaCl2*H2O and BaCl2*2H20. Do I have to do something to get just BaCl2 as an option? Thanks Tom!
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Hi Tom, Thanks again for all you help! Now can you walk me through the steps of a BaCl2 titration into this system? Best,
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If I have a partial pressure of 8mbar CO2, how do I translate that to the "log of a fugacity"? Is that an equation? How did you get -3.5?
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Hi again Tom, Thanks for your patience with my many question! So I just talked with my supervisor - as for cations both Ca++ and Mg++ can be varied, as they are supersaturated in our solution. We don't know the HCO3-, can it calculate it?
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Great point - I think part of the problem is that these are all the set concentrations of things we could measure. There's probably something else in the system, but we don't know what...
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Hi Tom, Thanks for getting back to me. So the problem is that all those concentrations must be pretty much set. I can't allow say Na+ to change. What do you suggest I use that's not already in the picture?
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Thanks Tom! So I've set HCO3- to charge balance, now I have this error: Residuals too large, 663-th interation Largest residual(s): Resid Resid/Totmol Cbasis -------------------------------------------------------- HCO3- 0.0002174 1.723e+200 4.703e-203 -------------------------------------------------------- 8-31-09 Run.rea
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For some reason I'm getting this error message anyways: Caution: molality of Cl- component forced negative by charge balance: -0.0002024 *N-R didn't converge after 999 its., maximum residual = 1, Xi = 0.0000 Largest residual(s): Resid Resid/Totmol Cbasis -------------------------------------------------------- ClO4- 2.072e+006 1 3.293e-009 --------------------------------------------------------
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Okay, I understand the difference btw an open and closed system. But I have somewhat of an interesting case - where the solution is exposed to and interacting with external atmosphere which has circulated into the headspace of the beaker. But it's not an open system in a traditional sense... Would this still be considered an open system or closed?
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Hi, So Cl- usually comes up as the thing to be used to charge balance. But my Cl- concentration is more or less fixed, so I don't want to use that. But what else can I use that won't change my other fixed concentrations? Thanks!
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Thanks! So finally I want to try the model using the pH we measured. The pCO2 is still the same (8.3mbars). How can I input this, so that it stops yelling at me that I need HCO3-? (I was guessing at HCO3- previously so I want to take this value out).