Experiment 10 - Vitamin C Determination

Postlab Questions:

Part A - Preparation of Standard Thiosulphate, S₂O₃^2-, Solution

1. Determine the concentration of sodium thiosulphate solution in g/mL.
2. Determine the concentration of sodium thiosulphate solution in g/L.
3. Determine the concentration of sodium thiosulphate solution in moles/L.
   

Part B - Standardization of the Iodine Solution

1. How many moles of S₂O₃^2- ions is available in the flask?
2. Write the balanced equation for the reaction which occurs.
3. How many moles of iodine, I₂, is added in the titration?
4. What is the volume of iodine solutioin added in the titration?
   (Note: What is the average titration volume?)
5. What is the molarity of the iodine, I_2, solution?

Part C - Vitamin C Determination in Fruit Juice

1. How many moles of iodine, I_2, is added in the titration?
2. Write the balanced equation for the reaction which occurs.
3. How many moles of vitamin C is available in the flask?
4. What is the volume of fruit juice used?
5. How many moles of vitamin C is in 100 mL of the fruit juice?
6. How many milligrams of vitamin C is in 100 mL of the fruit juice?