The number of moles of mercury can you get you collect and process the entire volume of 1250 m3 of the water in the pond is 8.7 × 10^-5 moles.
First, we must convert the concentration of mercury in the pond to molar concentration using the relation;
Mass concentration = Molar concentration × molar mass
Molar concentration = Mass concentration /molar mass
Molar mass of mercury = 201 g/mol
Molar concentration = 14 × 10^-9 g/201 g/mol = 6.97 × 10^-11 M
Volume of solution = 1250 m3 or 1250000 L
Number of moles = concentration × volume
Number of moles = 6.97 × 10^-11 M × 1250000 L
Number of moles = 8.7 × 10^-5 moles
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