# Calculating Molarity?

I don t understand what I m supposed to do here?

In the procedure for "Experiment 1" on p. 230 of the lab manual, the student records the concentration of the stock solution of H2O2 to be 0.965 M. The student proceeds to prepare the reaction solution as stated in the lab manual: They add 10.0 mL of 0.10 M potassium iodide and 15.0 mL of distilled water to their flask. They then add 5.0 mL of the stock H2O2 solution and mix the solution to initiate the reaction. Calculate the molarity of I- in the initial reaction solution. Do not include the units with your answer.

### 1 Answer

- davidLv 72 months agoFavorite Answer
Assume volumes are additive

Total Vol = 10.0mL + 15.0mL + 5.0mL = 30.0 mL

now use the dilution equation

M1V1 = M2V2

10.0 X 0.10 = M2 X 30.0

M2 = 0.033333 M <<<< round as needed

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