A #5*g# mass of sodium chloride, and an #8.2*g# mass of sodium sulfate are dissolved in a #200*mL# of aqueous solution. What is #[Na^+]#?

1 Answer
Sep 18, 2017

Well I make #[Na^+]=1.00*mol*L^-1#

Explanation:

#"Moles of NaCl"=(5.0*g)/(58.44*g*mol^-1)=0.0856*mol#.

#"Moles of"# #Na_2SO_4=(8.2*g)/(142.04*g*mol^-1)=0.0577*mol#.

And thus #[Na^+]=(0.0856*mol+2xx0.0577*mol)/(200*mLxx10^-3*L*mL^-1)#

#=??*mol*L^-1#.

Why did I double the molar quantity with respect to #Na_2SO_4#. Did I make a mistake?