I am a student in my last year of high school and currently making a research on how to find sulfites in dried fruits. I've collected data and different methods online and combined few of them into one. In my method I use hydrogen peroxide and barium chloride to create a white precipitate (result should be barium sulfite).
But the problem is that I never get any precipitate. During my research it mentioned that I was to leave the dried fruit in distilled water over night (I used dried apricots). I had 26g, 30g, 40g of dried apricot in 100mL of distilled water. Once done, I filter out all of the liquids into a different beaker. Then filter it using filter paper. Once done I separate them into different beakers to test. And this is where I find the problem, I've done 6 trials so far, and all 6 have failed. Because I don't know what amount of H2O2 or what amount of the concentration I need to put into the apricot liquid for it to properly react, or for how long I should leave it in for it to react (I've waited 3 and 5 minutes). I'm then supposed to drop a single drop of barium chloride into the solution to produce the white precipitate. But so far I haven't gotten any sign of any precipitate. I've tried different amounts of H2O2 (1mL, 5mL, 10mL, 15mL, 20mL & 25mL with a 35% concentration in the first trials but rest of the trials were with a 3% concentration). Each with a drop of barium chloride. Seeing that they did not react to a drop, I tried to use 5 drops each on the first few trials. Yet I still got no reaction.
Could I get some help or advice please?