A 500 gm of toothpaste sample has 0.2 g of fluoride concentration. What is theconcentration of fluoride in terms of ppm level?

This is a way of expressing very dilute concentrations of substances. Just as per cent means out of a hundred, so parts per million or ppm means out of a million. Usually describes the concentration of something in water or soil. One ppm is equivalent to 1 milligram of something per liter of water (mg/l) or 1 milligram of something per kilogram soil (mg/kg).
the concentration of fluoride in terms of ppm level
PPM=no of parts of the component/total no of parts of allcomponent *10^6
=.2/500 *10^6
=400ppm

Dear Student,
Please find below the solution to your problem.

This is a way of expressing very dilute concentrations of substances.
Just as per cent means out of a hundred, so parts per million or ppm means out of a million.
Usually describes the concentration of something in water or soil.
One ppm is equivalent to 1 milligram of something per liter of water (mg/l) or 1 milligram of something per kilogram soil (mg/kg).
The concentration of fluoride in terms of ppm level PPM=no of parts of the component/total no of parts of allcomponent *10^6
=.2/500 *10^6
=400ppm

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