Chemistry · Environmental Chemistry
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A water sample contains 3.8 x 103g of mercury per kilo gram of the sample. What is the concentration of mercury in parts per million?
- A
3.8 ppm
- B
38 ppm
- C
0.38 ppm
- D
380 ppm
The concentration of mercury is calculated by the formula:
ppm = (mass of solute / mass of solution) x 106
Given 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.
This is the correct answer. Convert grams to parts per million by dividing the mass of mercury by the mass of the sample and multiplying by 1,000,000.
This option is incorrect. It results from a miscalculation or misunderstanding of the conversion process.
This option is incorrect. This value is too low and likely results from incorrect unit conversion.
This option is incorrect. It overestimates the concentration by a factor of 100 due to a calculation error.
Tagged under Chemistry · Environmental Chemistry · 2016