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Pure NaCl is not used in a Down's cell - VCE - SSCE Chemistry - Question 17 - 2002 - Paper 1
Question 17
Pure NaCl is not used in a Down's cell. The liquid that is in a Down's cell is a mixture of CaCl₂ and NaCl. The CaCl₂/NaCl mixture is used instead of pure NaCl becau... show full transcript
Worked Solution & Example Answer:Pure NaCl is not used in a Down's cell - VCE - SSCE Chemistry - Question 17 - 2002 - Paper 1
Step 1
D. enables the process to be carried out at a lower temperature.
Answer
The mixture of CaCl₂ and NaCl is preferred in a Down's cell as it lowers the melting point of the electrolyte solution. This allows the electrical process of electrolysis to occur more efficiently at lower temperatures, which enhances the overall yield of the chemical products, such as chlorine gas and sodium. Lower operational temperatures not only improve safety but also reduce energy costs associated with heating.