Determination of dissolved oxygen by colorimetric titration: the Winkler method
Equipment and reagents
- Standard laboratory equipment, in particular: analytical scale, burette, glassware.
- Large crystallizer
- Sodium hydroxide ash pellets
- Solid manganese chloride MnCl2
- Sulfuric acid 9 mol/L
- Solid potassium iodide KI
- Starch in solution (mix 5 g of soluble starch with 30 mL of water and add this mix to 1 L of boiling water; boil for 3 minutes then leave to cool down)
- Sodium thiosulfate 0.01 mol/L (aqueous solution)