cwf09
Harmless
Posts: 1
Registered: 20-10-2011
Member Is Offline
Mood: No Mood
|
|
Distribution Diagram of Cr(VI)
Hi, I'm a geology major and currently taking a geochemistry class. This problem has been vexing me. I made an alpha plot for the various
species(see the attached image) but the pH is far too low for the main species(vs. published data). I've been working on this for a while, and I'm
kind of lost at the moment. Any books that you can recommend that will help? How would you guys approach this problem?
3. Make a distribution diagram for the various Cr(VI) species as a function of pH at CrT=1, 10-2 and 10-4M. Neglect activity corrections.
Equilibria: CrO42-+H+=HCrO4-; logK1=6.5
HCrO4-+H+=H2CrO4; logK2=-0.8
2 HCrO4-=Cr2O72-+H2O logK1a=1.52
Cr2O72-+ H+=H Cr2O7- logK2a=0.07
[Cr]T=[CrO42-]+[HCrO4-]+2[Cr2O72-]+2[HCr2O7-]
|
|
|
DDTea
National Hazard
Posts: 940
Registered: 25-2-2003
Location: Freedomland
Member Is Offline
Mood: Degenerate
|
|
It looks like you forgot to attach the image of your work. Would you mind including your calculations as well?
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
