A more rigorous theory of pH

Electroneutrality condition

Exercise 3

    

The label of a mineral water indicates the mass concentrations (mg/L) of its major ions:

Given the precision of the measurements, check if the electroneutrality of the solution is verified.

$[Ca^2+ ]$ $=$ $0.259 \frac{mmol}{L}$, $[Mg^{2+}]$ $=$ $0.25 \frac{mmol}{L}$, $[Na^+]$ $=$ $0.34 \frac{mmol}{L}$, $[K^+]$ $=$ $0.14 \frac{mmol}{L}$, $[Cl^-]$ $=$ $0.21 \frac{mmol}{L}$, $[NO_3^-]$ $=$ $0.064 \frac{mmol}{L}$, $[SO_4^{2-}]$ $=$ $0.070 \frac{mmol}{L}$, $[HCO_3^-]$ $=$ $1.05 \frac{mmol}{L}$, Verification: $2\cdot 0.259$ $+$ $2\cdot0.25$ $+$ $0.34$ $+$ $0.14$ $\approx$ $0.21$ $+$ $0.064$ $+$ $2\cdot 0.070$ $+$ $1.05$