What is the molar concentration of potassium ion in a solution that is #73*"ppm"# with respect to #K_3[Fe(C-=N)_6]#?

1 Answer
May 18, 2017

Answer:

#"1 ppm"# specifies #1*mg*L^-1# of solution.........

Explanation:

And thus in #1*L# of solution, we have............

#((73xx10^-3*g)/(329.24*g*mol^-1))/(1*L)=2.21xx10^-5*mol*L^-1# with respect to #K_3[Fe(C-=N)_6]#.

Since that are 3 moles of potassium ion per mole of salt, #[K^+]=6.7xx10^-5*mol*L^-1#.

You might be tempted to argue that I should have accounted for the solution density in these calculations. Even if these data were available, at #"ppm"# concentrations they would make negligible difference, and so may be ignored.

If I dissolved #1*g# of common salt, #NaCl#, in a #1*L# volume of water, what would be the #"ppm"# concentration?