From: A novel screening protocol for the isolation of hydrogen producing Chlamydomonas reinhardtiistrains
 | Reaction | Comment |
---|---|---|
1) oxygen fixation | Mn2+ + 2OH- → Mn(OH)2 4Mn(OH)2 + O2 + 2H2O → 4Mn(OH)3 (s) | Dissolved oxygen is fixed with manganese chloride |
2) Manganese dissolving | 2Mn(OH)3 + 2I- + 6 H+ → 2Mn2+ + I2 + 6H2O | Acidifying the solution by adding H3PO4 dissolves the brown precipitate. Mn(III) cations are liberated which oxidize added iodide to iodine |
3) Starch addition | Â | Elementary iodine intercalates within starch helices turning the solution into a dark-blue color |
4) Titration | I2 + 2S2O32- → 2I- + S4O62- | The oxygen concentration in each well can be determined by titrating with sodium thiosulfate |