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So basically I'm forced to take this chemistry course when I have no chemistry background. Now I'm struggling with the assignment. I was wondering if anyone could teach me how to do some of these questions

1. Estimate the level of saturation of lake water containing 11.8mg/L of dissolved O2 at 14C. Kh (14C) = 1.53*10^-3 mol L^-1 atm ^-1. Comment Your Answer.

2. Calculate the pH of a lake (at 25C) in equilibrium with atmospheric carbon dioxide containing 750 ppmv of CO2 (Year 2100) and soid calcium carbonate. Calculate the alkalinity and [Ca 2+] in the lake

3. What is the calculated value of the partial pressure of O2 in acid mine water at pH = 2.0 in which: [Fe2+] = [Fe3+]


these questions are equivallent to a 4th year University course, so ya please help me out and take a stab at hi lol


Thanks in advance

Here are some equations that might help you along :

1) for oxygen saturation level : http://en.wikipedia.org/wiki/Oxygen_saturation

2) for alkalinity : http://en.wikipedia.org/wiki/Alkalinity
also, for calcium carbonate reaction with CO2 and water :
http://en.wikipedia.org/wiki/Calcium_carbonate
you will need to know a little bit about chemical equilibrium:
http://en.wikipedia.org/wiki/Chemical_equilibrium

3) for partial pressure calcs :
http://en.wikipedia.org/wiki/Partial_pressure
(note for oxygen you probably will probably have to use Henry's law)
(also note that pH is the -log of the concentration of H+ ions in your solution. I don't know how they correlate that to an acid mine though... )

I think your textbook should have a more in depth explanation of this. What class is this?

Both of your avatars were in sync.

GODDAMN that was weird.

it's the panda fox boogie

That looks like Gen Chem.

Yuck.

its Gen Chem II which isn't that high as far as chem classes go but its mostly for ppl going into a scientific field...alot of ph and acid base formulas...

XemnasXD wrote:its Gen Chem II which isn't that high as far as chem classes go but its mostly for ppl going into a scientific field...alot of ph and acid base formulas...

isn't general chem the same thing as AP chem in high school? Cause the book were using here says "general chemistry 8th edition"

anyways, your better off asking a science forum or something. I doubt anyone here has taken 4 years of college chemistry

AP Chem would be the same as Gen Chem I, theoretically, but that really depends on the college....either way those problems aren't worth 4 years of college, i learned to do them the second semester of my first year...

Thx for the quick replies, although only one guy helped XD in which our avatar synced lol

but ya this is Environmental Analytical chem, which is like mostly on pollutants and contaminants in natural ecosystems


EDIT: btw, thx chickenfeather

lol destruction no one here knows that shit u have better luck posting in some science forum, we are just gamers of avg intelligence and there are some like me that took a chem class where they teach basic shit which most of us probably forgot already like i did.

PM Goobronicus on the forum, his major is chemistry, he might be able to help. I'm not sure if he visits OTL though.

Thxs guys I'll try to figure this out lolz

but anyone can recommend me a science forum???

Oh god. I took chemistry on my second sem in college and I hated every minute of it. Still passed with flying colors although everything I know about it came out of my colon a long time ago.

I would trade you my chemistry book for some cookies though

Weren't you given formulas for these problems? I kind of forget most of this. I'm studying organic chem right now which uses no stoichiometry at all.

Locketart wrote:Weren't you given formulas for these problems? I kind of forget most of this. I'm studying organic chem right now which uses no stoichiometry at all.

I wasn't given any formulas because its a 4th year course its expected for students to know these stuff but too bad I'm not one....

ARK! I hate Chemistry!

Locketart wrote:Weren't you given formulas for these problems? I kind of forget most of this. I'm studying organic chem right now which uses no stoichiometry at all.

Organic chemistry at low levels teach stuff mostly about naming compounds and the different rules. At higher levels we gotta deal with different mechanisms, Spectroscopy: Infra-red, NMR (proton and C13), and Mass Spectrometry.

@OP: I did these questions a year ago. I don't actually remember how to do them without formulas. So, if you find out the formulas or some kind of reaction mechanism or equilibrium equation, I might be able to help.
I reckon, there are many ways to solve these kind of questions.