Method: Hach LeadTrak Fast Column Extraction Method Range: 5-150 ppb lead in water Kit includes a 10 mg/L lead standard = 10,000 ppb lead. Also need distilled or deionized water.
Test 1: 0 and 50 ppb Sample 1 was a "blank" 0 ppb sample which was just 100 mL of distilled water. Sample 2 was a 50 ppb solution prepared by adding 0.5 mL of the lead 10 mg/L standard to 100 mL distilled water. Followed the LeadTrak Fast Column procedure for both samples. In the first test, ended up blanking the colorimeter with water and measuring absorbance at 470 nm with the samples before and after decolorizing solution was added.
Test 2: 0 and 150 ppb Sample 1 was a "blank" 0 ppb sample which was just 100 mL of deionized water. Sample 2 was a 150 ppb solution prepared by adding 1.5 mL of the lead 10 mg/L standard to 100 mL deionized water. Followed the LeadTrak Fast Column procedure for both samples. In the second test, I took the 25 mL eluted sample and poured 10 mL into 2 tubes for each sample. To one of the tubes, added 3 drops of decolorizing solution. The sample with the decolorizing solution was used to zero the colorimeter and the sample without decolorizing solution was measured.
Test 3: 0 and 150 ppb repeated Same method as Test # 2. Measured absorbance at 470 nm in the colorimeter and also using an Ocean Optics Spectrophotometer.
Test 4: 0, 50, 100 and 150 ppb calibration curve Same method as usual. Measured absorbance at 470 nm in the colorimeter and and also using Ocean Optics Spectrophotometer. Note, for the Ocean Optics, data was less noisy as we used averaging (n=10) in the ocean optics software.
Test 5: 100 ppm standard and tap water
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