posted by Martin on .
You wish to prepare 1 L of a 0.02 M potassium iodate solution. You require that the final concentration be within 1% of 0.02 M and that the concentration must be known accurately to the fourth decimal place. How would you prepare this solution? Specify the glassware you would use, the accuracy needed for the balance, and the ranges of acceptable masses of KIO3 that could be used.
(a) To make this solution (ideally) you would need ________ grams of potassium iodide dissolved in enough water to make up 1 L of solution.
fill in the blank
(b)What is the least accurate balance that could be used to make this solution?
1 - a mass spectrometer (accuracy = 0.2 µg)
2 - an electronic balance (accuracy = 2 mg)
3 - a bathroom scale (accuracy = 2 kg) 4 - a kitchen scale (accuracy = 2 g)
5 - an analytical balance (accuracy = 0.2 mg)
6 - a triple beam balance (accuracy = 20 mg)
1 L of 0.02 M = M x L = 0.02 moles
moles KIO3 = grams/molar mass
0.02 x 214.001 = ?? grams KIO3.
Ideally this is what you want. You can work out the details (I would do the percent by using +1% and -1% of 0.02 grams and recalculate).
what was the answer to the least accurate balance??