A current of 2.50 A is passed for 20.0 min through an aqueous solution that contains either Cd²⁺ or Sn²⁺ ions, but not both. After the electrolysis, 1.80 g of metal is collected at the cathode. Which metal is most consistent with these data?
a) Zn
b) Sn
c) Cd
d) Pb