Final answer:
The electrolysis of molten barium chloride involves reduction of barium ions and oxidation of chloride ions, requiring two electrons to move through the circuit for one unit of the reaction.
Step-by-step explanation:
During the electrolysis of molten barium chloride (BaCl2), barium ions (Ba2+) are reduced at the cathode, and chloride ions (Cl-) are oxidized at the anode. The half-reactions, showing the movement of electrons through the circuit, are as follows:
- Cathode (reduction): Ba2+(l) + 2e- → Ba(l)
- Anode (oxidation): 2Cl-(l) → Cl2(g) + 2e-
The overall cell reaction is obtained by combining the half-reactions and balancing the electrons:
Ba2+(l) + 2Cl-(l) → Ba(l) + Cl2(g)
For each mole of barium ions reduced, two electrons are involved in the transfer. Similarly, for each mole of chlorine gas produced, two electrons are given up by chloride ions. As such, there would be two electrons that moved through the circuit for one unit of the reaction to occur.