A water sample contains 3.8 x 10^3g of mercury per kilo gram of the sample. What is the concentration of mercury in parts per million?
Correct answer: A. 3.8 ppm
- A. 3.8 ppm
- B. 38 ppm
- C. 0.38 ppm
- D. 380 ppm
Explanation
The concentration of mercury is calculated by the formula:ppm = (mass of solute / mass of solution) x 106Given that you have 3.8 x 103g of mercury per kilogram of the sample, first convert this to the same units: 3.8 x 103 g/kg is equivalent to 3.8 g/kg. Since 1 kg equals 1,000,000 mg, the concentration is (3.8 / 1000) x 106 = 3.8 ppm.Other options are incorrect due to calculation errors or misinterpretation of the conversion factor to ppm.
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