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Organoid

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## Homework Statement

Hello,

This week I ran an AA Spectroscopy experiment in my university, in which we had to analyze the percentage of Copper in a metal coin, and the containment of Iron in morning cereal.

We used 2 standard solutions of 1 and 10 ppm (containing both Copper and Iron), and exprimented a few diluted solutions of the extracted Copper and Iron from the substances.

The results we received were an average value and standard deviation of the 3 tests run by the machine.

## Homework Equations

My question is: what do the

**concentration results**that the machine provides us with

**mean**? i.e. if 1 and 10 ppm standards had an average of 0.525 and 1.426 respectively, and the diluted solutions (x10, x100, x1000) had an average of 10.72, 4.094 and 2.644 respectively, how can I analyze these results to calculate the original conc. in the original substance?

## The Attempt at a Solution

I've generated a standard curve using the standards' results and reveied a linear-fit equation of the graph with a matching slope.

I know that the equation connecting those variables is AA = K x C, (where AA=absorbance, k is the trend line's slope and C is the conc.) but when I tried to apply my results of the diluted solutions to that equation, and by multiplying by the dilution factor, they don't make sense. Each solution gives different concentration of the original solution.

Am I analyzing my results using the standard curve wrong?

I'd appretiate any help, thank you.