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.
WBBSE
Class X
Physical Science
Metallurgy
02 Mark
2024
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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