I'm probably asking a dumb question, but can this method used to standardise potassium iodate? If not, do you know of any methods to standardise potassium iodate?
1. Obtain about 100 mL of the thiosulfate solution in a clean, dry 250 mL beaker. Cover the beaker with a watch glass or Parafilm to protect the solution from contamination. 2. Set up a 50 mL buret using a ring stand and buret clamp. Rinse the buret three times with about 10 mL of Thiosulfate solution each time. Drain the rinse liquid into a beaker and discard in the sink. Wash the waste down the drain with water. Fill the buret, drain out a couple of milliliters quickly to remove the air bubble in the tip, and take an initial reading to the nearest 0.01 mL. Don’t forget to record this value in your notebook. Set up a stir plate if desired. 3. Obtain about 100 mL of 0.0100 M KIO3 solution in another clean, dry 150 mL beaker. Rinse a 25 mL pipet with the solution (your instructor will show how to use less than 25 mL of rinse liquid) 4. Then pipet 25.00 mL of the KIO3 solution into a clean 250 mL Erlenmeyer flask. (Note: This flask need not be dry, but must contain only deionized water.) If enough flasks are available, pipet 25.00 mL of the solution into each of three flasks. 5. Working with one flask at a time, add about 25 mL of deionized water followed by about 1 gram of KI (the potassium iodide can be weighed in a clean, dry 50 mL beaker on the top-loading balance). Swirl to mix. Then add about 10 mL of 1 M HCl, mix and titrate immediately with thiosulfate. Do not stir too vigorously with the magnetic stirrer and therefore introduce a lot of air into the solution. Iodine might air-oxidize, giving a false value for the analysis. 6. When the solution in the Erlenmeyer flask becomes a yellow-orange color, interrupt the addition of titrant and add about 2 mL of starch solution. The solution will become blue-black in color. Now continue to add titrant slowly until the blue-black color disappears, leaving a colorless solution. This is the end point in the titration. Don’t forget to read the buret and record the value in your notebook. 7. Refill the buret with thiosulfate solution and prepare a second 25.00 mL sample of Iodate solution. Repeat the titration.
Yes, specifically sodium thiosulfate (Na2S2O3) that is approximates 0.05 M, though we've found the solution degrades too much after 48 hours to be useful
I'm probably asking a dumb question, but can this method used to standardise potassium iodate? If not, do you know of any methods to standardise potassium iodate?
this music rocks
I
agree
thanks?
Can u have sop for preparation and standardization of 0.05M pottassium Iodate Solution
1. Obtain about 100 mL of the thiosulfate solution in a clean, dry 250 mL beaker. Cover the beaker with a watch glass or Parafilm to protect the solution from contamination.
2. Set up a 50 mL buret using a ring stand and buret clamp. Rinse the buret three times with about 10 mL of Thiosulfate solution each time. Drain the rinse liquid into a beaker and discard in the sink. Wash the waste down the drain with water. Fill the buret, drain out a couple of milliliters quickly to remove the air bubble in the tip, and take an initial reading to the nearest 0.01 mL. Don’t forget to record this value in your notebook. Set up a stir plate if desired.
3. Obtain about 100 mL of 0.0100 M KIO3 solution in another clean, dry 150 mL beaker. Rinse a 25 mL pipet with the solution (your instructor will show how to use less than 25 mL of rinse liquid)
4. Then pipet 25.00 mL of the KIO3 solution into a clean 250 mL Erlenmeyer flask. (Note: This flask need not be dry, but must contain only deionized water.) If enough flasks are available, pipet 25.00 mL of the solution into each of three flasks.
5. Working with one flask at a time, add about 25 mL of deionized water followed by about 1 gram of KI (the potassium iodide can be weighed in a clean, dry 50 mL beaker on the top-loading balance). Swirl to mix. Then add about 10 mL of 1 M HCl, mix and titrate immediately with thiosulfate. Do not stir too vigorously with the magnetic stirrer and therefore introduce a lot of air into the solution. Iodine might air-oxidize, giving a false value for the analysis.
6. When the solution in the Erlenmeyer flask becomes a yellow-orange color, interrupt the addition of titrant and add about 2 mL of starch solution. The solution will become blue-black in color. Now continue to add titrant slowly until the blue-black color disappears, leaving a colorless solution. This is the end point in the titration. Don’t forget to read the buret and record the value in your notebook.
7. Refill the buret with thiosulfate solution and prepare a second 25.00 mL sample of Iodate solution. Repeat the titration.
Against thiosulphate?
Yes, specifically sodium thiosulfate (Na2S2O3) that is approximates 0.05 M, though we've found the solution degrades too much after 48 hours to be useful
Alright, thank you. I have 2 litres of 0.0541 mol/L sodium thiosulphate I made from solid that'll work
What is the indicator used?
1% Starch solution (added after the solution turns amber/light yellow)
@@ChemicalAlchemist thank you sir