A positively charged sol (40.0 mL) is just coagulated by 8.0 mL of 0.25 M $Na X_{2} SO X_{4}$ solution. The effective ion is the anion. Taking the concentration of the coagulating ion to be that in the final mixture, calculate the flocculation value of $SO X_{4} X^{2 -}$ ions in mmol per litre of the final mixture (two decimals).

Numerical answer type, answer in mmol/L, tolerance 0.02.

Answer: 41.67 mmol/L

Moles of sulfate

= 8.0 \times 0.25 = 2.0

mmol. Final volume

= 40.0 + 8.0 = 48.0

= 0.0480

L. Concentration

= 2.0/0.0480 = 41.67 mmol/L