Need Help With This Chemistry Question,chem Animals Only- 10 Points To Best Answer! ?

You wish to prepare 1 L of a 0.02M potassium idoate solution. You require the final concentration to be within 1% of 0.02M, and that the concentration be known accurately to 0.0001M.
Describe how you would make the solution, and specify the precision of your volumetric glassware, and balance.
What is the acceptable range of mass of iodate you can use?

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One Response to “Need Help With This Chemistry Question,chem Animals Only- 10 Points To Best Answer! ?”

  1. I’m guessing that you must be taking analytical chem. :)
    Now, this question requires you to look up tables of errors in a book or given to you somehow for the glassware given. Of course, this means you’ll first need to weigh potassium iodate on an analytical balance (0.02 moles of it, which you can find in grams by multiplying by its molar mass, note that there is error with molar masses too!), then stick it in a 1 L volumetric flask. Fill it up with distilled by using a known volumetric pipet x number of times (depends on size of pipet given to you).
    if this error is too high or too low, use a smaller flask and or pipet then transfer to another flask (to dilute), etc. Every size has a different amount of measurement error associated with it.
    Remember, this question completely depends on what the errors were given or associated with your glassware!!! (probably from a table or textbook you have)
    Notice, the errors comes from everything you used to measure. That means: balance, pipet, flask and molar mass used to measure grams of your potassium iodate
    So you have to do a lot of error calculations using the partial deritvative method (propagation of errors) or some other method you learned in class. Then calculate your relative standard deviation (in percent) to make sure it is within 1%. If not, use different glassware to make that solution to get a lower error.