Question

1. Calculate the amount of fluorescein (MW 332.31) you will need to make 10 mL of 15 mM solution in ethanol (EtOH).
My answer:0.05 g
2.Using Equation C1V1=C2V2 calculate the volume of stock solution (15 mM) you need to make 1 mL of each working solution concentration: 0 mM and 0.25 mM. Remember to convert your volumes to microliter.
My answers:
volume for 0mM --> 0 microliter
volume for 0.25 mM--> 16.67 ~ 17 microliter
3. Calculate the volume of DI H2O needed for each. Remember that this volume will be the total final volume minus the volume of stock solution you calculated.
My answers:
volume of water for the 0 mM --> 10,000 microliter subtract 0 microliter = 10,000 microliter


volume of water for the 0.25 mM --> 10,000 microliter subtract 17 microliter = 9983 microliter

Answer 1

.015 mols/liter * .01 liter = .15 mols
= .00015*332 = .0498
agree