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Iodometric Titration Tutorial


-Introduction

-Calculating moles of KIO3 required.

-Calculating concentration of KIO3 solution.

-Calculating mass of KIO3 to prepare solution.

-Conclusion

-Practice Question: Virtual Lab



Experiment 9 Iodometric Titration Online Tutorial >> Preparation of a KIO3 Standard Solution >> Calculating the mass of KIO3 required to prepare a standard solution.

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Exp 9: Iodometric Titration Online Tutorial - Preparation of a KIO3 Standard Solution

Step 3 - Calculating the mass of KIO3 required to prepare a standard solution.

Now that we have calculated the required concentration of potassium iodate, we need to prepare it from solid potassium iodate. In this tutor we will calculate the mass of solid KIO3 required to prepare 250 mL of standard solution.

What mass of potassium iodate needs to be weighed out to prepare 250.0 mL of the standard solution?

(Please give your answer to 4 significant figures)
Hint
grams KIO3
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The following tutor is a step by step walkthrough that shows the details of how to solve the above problem.


First, we'll calculate the number of moles needed to prepare the standard solution. How many moles of potassium iodate are needed to make 250.0 mL (0.2500L) of a 7.5714x10-4 M KIO3 solution?

(Please give your answer to 5 significant figures; for very small numbers, you may use scientific notation i.e. 6.3e-8)
Hint
moles KIO3
Next, we'll use the above number of moles to calculate the required mass of potassium iodate. How many grams of KIO3 are needed to prepare the standard solution?

(Please give your answer to 4 significant figures. Note: the molecular mass of potassium iodate is 214.0 g/mol)
grams KIO3
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Hint:
Molarity = moles/volume (in L) so moles = M x volume (in L). Using this conversion, now many moles are required?
 
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Hint:
Using this conversion, the result is
7.5714e-4 M KIO3 x 0.2500 L = 1.8929e-4 moles KIO3
 
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Hint:
Keeping in mind that moles (n) can be defined as:
moles (n) = [mass of compound] / [molecular mass of compund].
How can you use this relation to determine mass?
 
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Hint:
The relation can be rearranged as:
mass of compound = [moles (n)] x [molecular mass of compund].
Using this conversion, what is the mass of potassium iodate?
 
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Hint:
Using the above conversion and the given molecular mass, the result is: 1.8929e-4 moles x 214.0 g/mol = 0.04050 grams KIO3.
 
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Last Updated: Wednesday, January 11th, 2017 @ 10:31:25 am