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Topic: Concentration determination  (Read 1873 times)

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Offline IK

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Concentration determination
« on: January 25, 2017, 09:20:04 AM »
Dear all,

I have a solid pellet that is composed of component A,B,C and D. I am looking to determine the amount of component A in the pellet using UV. Therefore I dissolve the pellet in 4 ml water place it in UV and according to the calibration curve for component A I get the concentration of component A in g/L. The calibration curve is obtained using standards of component A.

My question is, is my determination of the conc of component A correct?

Offline Hunter2

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Re: Concentration determination
« Reply #1 on: January 25, 2017, 10:01:45 AM »
Looks  ok for me.

Online Borek

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Re: Concentration determination
« Reply #2 on: January 25, 2017, 10:05:53 AM »
Depends on whether B, C or D interfere.
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Offline Arkcon

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Re: Concentration determination
« Reply #3 on: January 25, 2017, 06:12:38 PM »
You have much more work to do before you can consider this done.  Like Borek: said, you haven't told us the properties of A, B, C, or D.  I don't know why you specify 4 ml of solvent, without telling us how big the "pellet" is.  Example, You will not find 1 gram of sucrose sealed in a 10g ball of iron-nickel-chromium alloy with 4 mL of water.  And I chose sucrose for a double incorrect answer -- since it doesn't have much UV absorbance. You haven't specified possible ranges for unknown, and how you will bracket with standards.  There are a number of non-ideal situations that may cause the plan to fail.  But in general, yes, a calibration curve of pure material will help.
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