Here's a cell you'll really like: The cell solution was made by mixing 25.0 mL of 4.00

Question:

Here's a cell you'll really like:

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 pK_a = 9.50

25.0 mL of KOH solution

The measured voltage was -0.440 V. 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^-₂+e^- ⇌ Cu(s) + 2CN^-. Suggested procedure: From E, find [CN]. From [CN], find pH. From pH, figure out how much OH had been added.