Give reasons for the following observations with regard to Hall's Heroult's process.
Cryolite and fluorspar are added to pure alumina.

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Solution

In order to lower the temperature of the mixture, cryolite and fluorspar are added to pure alumina.
Both the cryolite and fluorspar help in decreasing the fusion temperature of alumina from $2323 K$ to almost about $1140 K$ .
They help in increasing the conductivity of the mixture by decreasing the fusion temperature.

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in Hall-Heroult process to ____ m.p. and to ___________ electrical conductivity.

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Give reasons for the following observations with regard to Hall's Heroult's process.Cryolite and fluorspar are added to pure alumina.

Give reasons for the following observations with regard to Hall's Heroult's process.
Cryolite and fluorspar are added to pure alumina.