Solution Concentrations for FeSCN Equilibrium | Homework Problem

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AI Thread Summary
The discussion revolves around calculating initial concentrations of Fe3+ and SCN1- for various solutions, as well as the final concentration of FeSCN2+ in Solution #1A. The user initially attempted to calculate concentrations using incorrect unit conversions, leading to confusion. They later realized the need to apply the formula C1V1=C2V2 for accurate calculations, which considers the total volume of each solution. The user sought clarification on whether to include the volume of water in their calculations, indicating a misunderstanding of how to approach the problem. Ultimately, the user resolved their confusion independently.
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Homework Statement



a. the initial Fe3+ concentration of all of the solutions?
b. the initial SCN1- concentrations of Solutions #1A thru #5A?
c. the final concentration of FeSCN2+ in Solution #1A?

Homework Equations


The first column is the solution number, the second column is the volume of .100M Fe^3+, the third column is the volume of 5.00e-4M SCN^1-, the fourth column is the volume of water, and the fifth column is the total volume. All volumes are in units of mL.

1A 1.00 1.00 4.00 6.00
2A 1.00 1.50 3.50 6.00
3A 1.00 2.00 3.00 6.00
4A 1.00 2.50 2.50 6.00
5A 1.00 3.00 2.00 6.00

The Attempt at a Solution



For part a., I tried multiplying the given .100M by .001L to get .000100M. This, however, is incorrect according to my online assignment.

For part b., I did the same thing but with the SCN^1-. I multiplied the 5.00e-4M by the volume in mL. So for solution #1A, I did (5.00e-4M)*(.001L) and got .000000500M. This too is incorrect on both in both respects.

Part c is the same deal.

If anyone could help me with part a and maybe one from part b, I could do the rest. Any help is much appreciated.
 
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0.100M*0.001L is not 0.0001M, pay attention to units.

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methods
 
Okay. I'll rephrase what I think I should do. I think I need to use the formula C1V1=C2V2. Given the concentration of Fe^3+ and the volume of Fe^3+, what should I use for V2. Should it be the volume of Fe^3+ plus the volume of water. If that is the case they wouldn't all be the same since the volume of water differs for solutions 1-5, however, the question asks for one number.
 
Figured it out...nevermind
 
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