Electrolytic reduction of alumina to aluminium by Hall-Heroult process is carried out:A. In the presence of `NaCl`B. In the presence of fluorideC. In the presence of cryolite which forms a melt with lower melting temperatureD. In the presence of cryolite which forms a melt with higher melting temperature

Electrolytic reduction of alumina to aluminium by Hall-Heroult process

1.	Electrolytic reduction of alumina to aluminium by Hall-Heroult process is carried out:A. In the presence of `NaCl`B. In the presence of fluorideC. In the presence of cryolite which forms a melt with lower melting temperatureD. In the presence of cryolite which forms a melt with higher melting temperature
Answer» Correct Answer - C Cryolite is used to loweer the m.pt. of alumina as well as to make to good conductor of current

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Define molar conductivity of a solution and explain how molar conductivity changes with change in concentration of a solution for a weak and a strong electrolyte.
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Based on the data given below, the correcy order of reducing power is: `Fe_((aq.))^(3+) + e rarr Fe_((aq.))^(2+), E^(@) = +0.77 V` `Al_((aq.))^(3+) + 3e rarr Al_((s)), E^(@) = -1.66 V` `Br_(2(aq.)) + 2e rarr 2Br_((aq.))^(-), E^(@) = +1.08 V`A. `Br^(-) lt Fe^(2+) lt Al`B. `Fe^(2+) lt Al lt Br^-`C. `Al lt Br^(-) lt Fe^(2+)`D. `Al lt Fe^(2+) lt Br^(-)`
What are elementary reactions ?

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