Ag(s) | AgCl(s) | KCl (aq, saturated) || cell solution | Cu(s)
The cell solution was made by mixing
25.0 mL of 4.00 mM KCN
25.0 mL of 4.00 mM KCu(CN)2
25.0 mL of 0.400 M acid, HA, with pKa=9.50
25.0 mL of KOH solution
The measured voltage was -0.440V. Calculate the molarity of the KOH solution. Assume that essentially all copper (I) is Cu(CN)2-. A little HCN comes from the reaction of KCN with HA. Neglect the small amount of HA consumed by reaction with HCN. For the right half-cell, the reaction is Cu(CN)2- + e- ↔ Cu (s) + 2CN-.