Question

Cryolite is

• A. $Na_3AlF_6$ and is used in the electrolysis of alumina for decreasing electrical conductivity.
• B. $Na_3AlF_6$ and is used in the electrolysis of alumina for lowering the melting point of alumina only.
• C. $Na_3AlF_6$ and is used in the electrolysis of alumina for lowering the melting point and increasing the conductivity of alumina
• D. $Na_3AlF_6$ and is used in the electrolytic refining of alumina.

Answer 1

Answer: (C)

$Na_3AlF_6$ and is used in the electrolysis of alumina for lowering the melting point and increasing the conductivity of alumina

Answer 2

Cryolite is $Na _{3} AlF _{6}$ and used in the electrolysis of alumina for lowering the fusion temperature from $2050^{\circ} C$ to $950^{\circ} C$ and it increases the conductivity of alumina $Al _{2} O _{3}$ in Hall Heroult process.