Total Hardness Chemical Test Kit - HI3812
- Pre-made reagents for ease of use
- All reagents marked with expiration date and lot number for traceability
- Manual titration performed with calmagite indicator
The HI3812-100 are high quality reagents that are pre-measured, allowing for users to achieve fast and accurate total hardness measurements with the chemical test kit. These reagents follow the EDTA titration method to determine total hardness concentration as calcium carbonate (CaCO3). For determination of total hardness, the sample solution is first buffered to pH 10. The calmagite color indicator is added to form weak complexes at this basic pH with magnesium and calcium, forming a red colored complex. Addition of the EDTA titrant solution also forms complexes with the remaining free magnesium and calcium ions. Once all of the free magnesium and calcium ions have been complexed, the excess EDTA preferentially removes the ions bound with the calmagite color indicator, forming a stronger complex. The removal of these metal ions from the indicator causes a color change from red to blue, indicating the endpoint of the titration. The number of milliliters of titrant used to reach the appropriate endpoint will determine the total hardness as mg/L CaCO3. These reagents are designed to be used with samples that have an expected total hardness range of 0.0 to 30.0 mg/L and 0 to 300 mg/L CaCO3.
Specification
| SKU | HI3812 |
| Type | titration |
| Smallest Increment | 0.3 mg/L (ppm); 3 mg/L (ppm) |
| Method | EDTA |
| Number of Tests | 100 avg. |
| Ordering Information | HI3812 test kit comes with 30 mL hardness buffer, 10 mL calmagite indicator, 120 mL EDTA solution, 20 mL plastic beaker with cap, 50 mL plastic beaker with cap and 1 mL syringe with tip. |
| Reagent | HI3812-100 |
| Total Hardness Range | 0.0-30.0 mg/L (ppm); 0-300 mg/L (ppm) |
