Question

If 0.025 gram of Pb(NO3)2 is dissolved in 100. grams of H2O, what is the concentration of the resulting solution, in parts per million?
(1) 2.5 × 10–4 ppm (3) 250 ppm
(2) 2.5 ppm (4) 4.0 × 103 ppm

Answer 1

     The ppm is denifite by how many parts of the solute is present in a one million parts of the solution. Remembring that the solute should be in "mg" and the solutions shoud be in "kg".

$k= \frac{solute}{solution} \\ k= \frac{25}{0.1} \\ \boxed {k=250ppm}$

Number 3

If you notice any mistake in my english, please let me know, because i am not native.