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Spectrophotometric Determination of Manganese Pre Lab 1. Why do we use a "blank" solution as part...

Spectrophotometric Determination of Manganese Pre Lab

1. Why do we use a "blank" solution as part of the determination of the absorbance of unknown solutions?
2. What is the composition of the blank solution for this experiment?
3. For the second part of this experiment, a student made the following dilutions:
a) 10.0 mL of the stock solution was added to a 100.0-mL flask and diluted.

b) 20.0 mL of the stock solution was added to a 50.0-mL flask and diluted.

c) 30.0 mL of the stock solution was added to a 50.0-mL flask and diluted.

d) 40.0 mL of the stock solution was added to a 50.0-mL flask and diluted.
If the concentration of the stock solution is 2.5 x 10-4 M, what is the concentration of each of the diluted solutions?
a) ?

b) ?

c) ?

d) ?


4. Write the equation for Beer's Law. Identify each variable and the units that correspond to each.

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