Description
Features at-a-glance
- Complete setup
- All required materials are included with the test kit, such as the sample beaker, indicator and reagent bottles, spoon, and plastic pipettes.
- High resolution
- Readings from 0.00 to 2.00 mg/L are determined to 0.25 mg/L resolution.
- Readings from 0.0 to 10.0 mg/L are determined to 1.0 mg/L resolution.
- Replacement reagents available
- There is no need to buy a new kit when reagents are exhausted. The HI3844-100 can be ordered to replace the reagents supplied with the kit.
Significance of Use
Hydrogen peroxide (H2O2) is widely used as a disinfectant and as a bleach for textiles, wood pulp, and hair, just to name a few. It is also used as a substitute for chlorine in water and sewage treatment. Most common commercial forms are aqueous solutions containing about 6, 12 and 30% hydrogen peroxide and are referred to as “20-volume, ” “40-volume, ” and “100-volume” respectively, referring to the value of oxygen liberated when the solution is boiled. The Hanna test kit can quickly and easily determine concentration in water up to 10 mg/L of hydrogen peroxide. This is due to the fact that it is not affected by stabilizers, which are sometimes added to commercial hydrogen peroxide solutions.
In the HI3844 test kit, hydrogen peroxide reacts slowly with iodide in acid solution (Step 1); thus a 15 minute interval is required to allow the reaction to occur completely. The amount of iodine generated is equivalent to the hydrogen peroxide in the sample. The liberated iodine is then titrated with standard sodium thiosulfate solution that reduces the iodine back to iodide ions (Step 2).
Step 1: H2O2 + 2H+ + 2I– → I2 + 2H2O
Step 2: I2 + 2(S2O3)2- → 2I– + (S4O6)2-