This was extremely accurate and the experiment gave a

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approximately volume that was suggested that the color change would occur was of 27ml. This was extremely accurate and the experiment gave a volume of a range of in between 27.4ml-27.1ml for the endpoint to occur. Therefore, the calculated accuracy was 7.07x 10E-4 which is also less than 0.1%. The concentration predicted of
sodium thiosulfate was 0.1M and the calculated concentration of the three trials were 0.109M, 0.110M, 0.111M. The procedure was followed accurately and the results show the precision of the closely related calculations. Some errors that may have occured in the transition of the experiment may have been the loss of potassium iodide when transferring quantitatively to the volumetric flask. Also, delaying the titration with thiosulfate after the addition of iodide to the solution, this may have caused iodide to air oxidize. Recommendation: Each trial should be treated individually at a time to minimize the error from the air oxidation of iodide ion. This should prevent the titration error to become a significantly large number. Also, since iodine is slowly air oxidized in acid medium it is recommendable to not delay the titration with thiosulfate after the addition of iodine to the solution. The solutions should be prepared step by step to prevent any titration issues and contamination, due to many different chemicals that appear to be the same.

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