1) Electrochemical Measurement of Concentration

An electrochemical cell consists of a standard hydrogen electrode and a copper metal electrode.

a) What is the potential of this cell at 25°C if the copper electrode is placed in a solution in which [Cu2+] = 7.5×10-8 M?

b) The copper electrode of the above cell is placed in a solution of unknown [Cu2+]. The measured potential at 25°C is 0.109 V. What is [Cu2+] (in mol/L)? (Assume Cu2+ is reduced.)

c) A calibration curve to show how the cell potential varies with [Cu2+] may be constructed. A plot of cell potential (in V, with the same sense as in question 1) versus log10[Cu2+] should yield a straight line. What is the slope of this line?