Question

What is the melting point of alumina and how is the melting point reduced?

Hint:

Remember: The high melting point of alumina is reduced by dissolving it in molten cryolite, which lowers the temperature required for electrolysis.

Answer 1

The melting point of alumina (Al2O3) is very high, around 2072°C. This high melting point makes it difficult to directly use alumina in the electrolysis process. To reduce the melting point, alumina is dissolved in molten cryolite (Na3AlF6), which lowers the overall melting point of the mixture to about 950°C. This allows the electrolysis process to occur at much lower temperatures, making it more energy-efficient.