Question

To aid in the prevention of tooth decay, it is recommended that drinking water contain 0.800 ppm fluoride (F–). (a) How many grams of F– must be added to a cylindrical water reservoir having a diameter of 2.44 × 10^2 m and a depth of 17.27 m? (b) How many grams of sodium fluoride, NaF, contain this much fluoride?

Answer 1

diameter of the cylinder = 2.44 X 10 ^2 m

radius of the cylinder = 1.22 X 10 ^2 m

depth of the cylinder = 17.27 m

=8.075 X10^5 m3 = 8.075 X10^8 L

using the formula above we get, mass of gas = 646028.769g

for the

mass of fluoride = 646028.769g

hence mass of NaF required =( 646028.769g *42) / 19

= 1428063.595g