Given a #6.174*g# mass of sodium sulfate that is dissolved in a #1*L# volume, what is the concentration in terms of #"parts per million"# with respect to sodium ion?

1 Answer
Jul 31, 2017

Answer:

With respect to sodium ion, we have a #"2000 ppm"# concentration.

Explanation:

#"1 ppm"# specifies #1*mg# of solute per litre of solution......

We has #((6.174*g)/(142.04*g*mol^-1))/(1*L)=0.0435*mol*L^-1# with respect to sodium sulfate....

And thus #2xx0.04346*mol*L^-1=8.693xx10^-2*mol*L^-1#, with respect to sodium ion. Why did I double the concentration of sodium sulfate?

And thus, with respect to sodium ion, we have a concentration by mass of ........

#8.693xx10^-2*mol*L^-1xx22.99*g*mol^-1=2.000*g*L^-1#.

But #"1 ppm"# #=# #1xx10^-3*g*L^-1#, i.e. #1*mg*L^-1#, and thus we have.....

#2.000*g*L^-1xx10^3*mg*g^-1=2000*mg*L^-1-=2000# #"ppm"#.