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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: sarah9625 on November 11, 2007, 05:45:03 PM

Title: Phosphate determination
Post by: sarah9625 on November 11, 2007, 05:45:03 PM

I am doing a project in the lab to determine the phosphate concentration of a water sample. There are so many steps involved. Can someone point me in the right direction. I know that I will be making a reagent using 2.5g ammoniun molybdate in 30ml distilled water.Then mixing 0.125g ammonium metavandate in 30ml water, heating it, cooling it, then adding 33ml HCL. Then I will mix them and dilute to 100ml with water. What is this reagent for, when will I be needing it?
Then I have to prepare my standard phosphate sample using Anhydrous KH2PO4. How do I do this? And what is standard being used for?
Then I have to prepare my samples. How is this done? why am I having to prepare my samples? They are on liquid form already, hence, water is my sample. Then the procedure talks about sample digestion or acidifying the sample. Why is this being done, do I have to do digestion for a tap water sample?

I AM COMPLETELY LOST ON THIS WHOLE PROJECT. I HAVE SPENT THE LAST  WEEKS READING EVERY WEBSITE ON THIS LAB. thEY ARE ALL CONFUSING SINCE THEY ARE ALL DOING DIFFERENT THINGS AND USING DIFFERENT TECHNIQUES. I NEED SOME HELP, PLEASE!

Title: Re: Phosphate determination
Post by: sarah9625 on November 12, 2007, 05:03:23 PM

Here is the link to what I am doing:
http://quiz2.chem.arizona.edu/genchemlabs/104bsyllabus/ResearchProject/Phosphate/phosphate.pdf

Title: Re: Phosphate determination
Post by: ARGOS++ on November 12, 2007, 05:50:04 PM

Dear Sahra9625;

Your reference is with one exception identical to the one I have sent you by “private Forum mail”
So translation could really make sense, because it contains a Step by Step procedure.
So you can do it quasi analog (MV, Standards, Calibration, why, how).
For the formulas we have still to search.
But I translate it only if you would like to have it (with additional hints).


Good Luck!
                   ARGOS⁺⁺

Title: Re: Phosphate determination
Post by: sarah9625 on November 12, 2007, 06:16:07 PM

That would be GREAT if you could translate the step by step procedure portion at least. I would be greatful for that:)
Thanks

Title: Re: Phosphate determination
Post by: ARGOS++ on November 14, 2007, 01:00:19 PM

Dear Sahra9625;

Since a few days you have a “private Forum mail”.
I would like to know if I’m "clear" and "complete" enough!

Good Luck!
                   ARGOS⁺⁺

Title: Re: Phosphate determination
Post by: ARGOS++ on November 25, 2007, 03:19:49 PM

Dear Sahra9625;

As it seems you have lost your “child” (Your Question) and all your interest in it, I will give my translation un-corrected to the Forum to be not lost, - It’s a pity!

To all Other:
Please check if my translation needs some corrections, or if I have to spend more Hints or more Carifications. In case I will do.
The German origin can be found at:

"http://zaphod.gpi.uni-kiel.de/~mas/skript01.pdf (http://zaphod.gpi.uni-kiel.de/~mas/skript01.pdf)”     (at page 33, ff)

I hope it may be of help to others.
Thank you all for your help.

Good Luck!
                   ARGOS⁺⁺