The absorbance of a cationic iron(II) sample solution was measured in a spectrophotometer, but the instrument...

The absorbance of a cationic iron(II) sample solution was measured in a spectrophotometer, but the instrument returned an error because the absorbance was too high. The sample was then diluted by using a pipette to take 100.0 μL of the sample and injecting it into a cuvette already containing 2.00 mL of water (total volume is 2.00 mL + 100.0 μL). The absorbance value of the diluted solution corresponded to a concentration of 7.71×10⁻⁶ M . What was the concentration of the original solution?

Express the concentration to three significant figures with the appropriate units.

Expert Solution

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queen_honey_blossom answered 2 years ago

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