The goal of the experiment was to measure the voltage of cells with known concentrations. The Nernst Equation: Ecell = Eo - .0592/n ; was useed to calculate unknown concentrations from the measured voltages and observed polarities of galvanic cells. The concentrations were then used to calculate the values of the equilibrium constants for the formation of tetraammineezinc ion, and the dissolving silver chloride. The experiment was divided into five parts. Each part contained a discussion of the theory and calculations, which corresponds to the construction of the galvanic cell. The equation used for part D was:Kf=[Zn(NH3)2+] / [Zn2+] [NH4]4The equation used in part E was: Ksp = [Ag+] [Cl-]Procedure:Part A- A vial was filled half way with a 0.2M ammonium nitrate solution, and clamped onto a ring stand. A small wad of cotton was packed tightly into the bottom of a medicine dropper. The dropper was filled two-thirds of the way with 0.1M copper (II) sulfate. The dropper was placed into the ammonium nitrate solution, and a bit more copper (II) sulfate solution was added. A piece of copper was added to the dropper. A half cell containing 0.1M Silver Nitrate and a wire of silver medal was prepare vial with the copper electrode. The voltmeter leads were attached to the copper and sliver electrodes so there as a positive reading. The initial Ecell was recorded along with the polarity. The half-cell reactions and the equation for the spontaneous cell reaction were written. Finally, the Nernst Equation was used to calculate the Eo for the cell. Part B- The silver half-cell was replaced by a zinc half-cell. The half-cell was prepared from a dropper, wad of cotton, 0.1M zinc sulfate, and a zinc strip. The voltmeter leads were attached in order to get a positive reading. The Ecell and the polarity were measured and recorded. The half cell reactions and the equation for the spontaeous cell reaction were written. The Eo for the cell was calculated.Pa...
