Question

In one episode of the 1960s television sitcom, Gilligan’s Island, the famous "professor" constructed voltaic cells to use as substitutes for their radio’s dead batteries. A single D-cell has an emf of 1.5 V. Which scraps of metal from their damaged boat, the Minnow, could best be used to create a 1.5 V voltaic cell? Assume that coconuts make great beakers and that seawater is a terrific electrolyte. E°

a. Iron/iron(II) (the anchor) -0.44 V
b. Lead/lead(II) (fishing weights) -0.126 V
c. Silver/silver(I) (Mrs. Howell’s brooch) -0.799 V
d. Aluminum/aluminum(III) (the boat’s flagpole) -1.677 V

Answer 1

To replicate a 1.5 V D-cell battery, using Lead/lead(II) for the cathode and Aluminum/aluminum(III) for the anode from the boat scraps would be the most appropriate choice based on their standard electrode potentials, which when combined could yield the desired voltage for the voltaic cell.

Step-by-step explanation:

To create a 1.5 V voltaic cell from scraps of metal from their damaged boat, the Minnow, the most suitable metals would be Lead/lead(II) from the fishing weights and Aluminum/aluminum(III) from the boat’s flagpole. This is because we need to create a cell with an electromotive force (emf) similar to that of a single D-cell battery, which is 1.5 volts. By combining two half-reactions with different standard electrode potentials, we can achieve the desired total voltage.

Specifically, we would use the aluminum as the anode and the lead as the cathode. The standard electrode potential for lead is -0.126 V and for aluminum, it is -1.677 V. By combining these two metals in a voltaic cell, the difference in their potentials would be intended to approximate the 1.5 V of a D-cell.

Overall, the choice of metals for a voltaic cell is crucial to obtaining the correct voltage. The materials used, their inherent electrode potentials, and the way they react with the electrolyte will ultimately determine the cell's output voltage.