If 15 g of aluminum from an empty soda can could be used as an anode of a battery, how long
Could it supply a current of 10 amps?

Question

Quizplus · Accepted Answer

The reaction at the anode for aluminum is Al → Al³⁺ + 3e⁻. The molar mass of aluminum is 27 g/mol, so 15 g of aluminum is 0.556 mol. Each mole of aluminum provides 3 moles of electrons, so 0.556 mol of aluminum provides 1.668 mol of electrons. The charge of 1 mole of electrons is 96485 C (Faraday's constant), so 1.668 mol of electrons provides 161,000 C. At 10 amps, the time is 161,000 C / 10 A = 16,100 seconds, which is approximately 4.5 hours.

If 15 G of Aluminum from an Empty Soda Can