QQuestion
Why is dehydrated calcium chloride added during the extraction of sodium through electrolysis of sodium chloride ?
OR
Mention two ways of preventing the rusting of iron.
✓Answer
Dehydrated calcium chloride (CaCl2) is added during the electrolysis of sodium chloride (NaCl) because it lowers the melting point of sodium chloride. Sodium chloride has a high melting point, and adding CaCl2 helps to keep the electrolyte in a molten state at lower temperatures, making the process more efficient.
OR
Two ways of preventing the rusting of iron:
- Galvanization: Coating iron with a layer of zinc to protect it from exposure to moisture and air.
- Paint coating: Applying a layer of paint to prevent direct contact between iron and the environment.
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