Chemistry How Do You Calculate Iron Concentration in Tablets from AAS Data?

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The discussion focuses on using Atomic Absorption Spectroscopy (AAS) to analyze the iron concentration in three brands of iron tablets. The students prepared samples by dissolving tablets in hydrochloric acid and filtering the solution before measuring absorbance. Sample A showed an absorbance of 0.85 with an iron concentration of 4.7 ppm, while Sample B had an absorbance of 0.8 and a concentration of 0.6 ppm. To calculate the concentration of iron in the tablets, the molarity equation (n/v) is suggested, emphasizing the need to know the atomic weight of iron. The goal is to determine the amount of iron present in each tablet based on the prepared solutions.
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A group of students decided to use AAS to analyze three different brands of iron tablets to determine their content. They placed a tablet in a 100 mL beaker with 6 mol/L HCl and covered it with a watch glass and heated slowly for 15 min. They then filtered the solution into a 250 mL volumetric flask and topped it up to mark with distilled water.

They determined the absorbance of the sample and repeated the same process for the other two samples

Sample A: Absrobance =0.85 concentration of iron in solution = 4.7 ppm
Sample B Absorbance = 0.8 Concentration of iron in solution = 0.6 ppm

Calculate the concentration of iron in the tablet itself.

Homework Equations



Equations:
Molarity = n/v

The Attempt at a Solution


I have no clue what to do. If only somebody can point me in the right direction I would be very grateful.
 
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Obviously sample A and sample B are either of different brands or of different product editions. Helpful fact to know is that parts per million (abbreviated, "ppm") is nearly the same as milligrams per liter. You already know that the solutions prepared for each sample are 250 ml. each. You need to know the atomic weight of iron, which you can find in common reference works such as Periodic Table. You are interested in amount of iron in each tablet.

n/v ... How many moles of iron in how much volume of solution? Each 250 ml. solution contains the iron from the tablet sample.
 
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