[zeeshanef]

How melting point of sodium chloride is decreased when calcium chloride is added during preparation of sodium by [Down] cell?

[maivu]

Anode: (positive carbon electrode)
2Cl^-(l) → Cl₂(g) + 2e
Cathode: (negative iron electrode)
Na⁺(l) + e → Na(l)

Overall REDOX Reaction:
2Cl^-(l) + 2Na⁺(l) → Cl2(g) + 2Na(l)

The following is my suggestion. You should check it with your professor since I'm not an expert in Electrolysis.

You can think of how the Le Chatelier's principle is applied in here. When more Cl^- ions are added into the molten NaCl, the equilibrium is shifted to the right, forming more Na and Cl₂. The entropy of this reaction is positive since the system becomes more random. The system during this reaction will absorbs heat and deceases the temperature of molten.

[Borek]

You can think of how the Le Chatelier's principle is applied in here. When more Cl^- ions are added into the molten NaCl, the equilibrium is shifted to the right, forming more Na and Cl₂. The entropy of this reaction is positive since the system becomes more random. The system during this reaction will absorbs heat and deceases the temperature of molten.

Please don't answer questions when you have no idea what you are writing about. This word salad is not helpful.