MolSynapsequestion bank

MolSynapse / Question bank / p-Block Elements: Groups 13 and 14 / Aluminium compounds and alums

JEE Main levelSingle correct optionDifficulty 2 of 3pb136

In the Hall-Heroult process, cryolite $Na X_{3} AlF X_{6}$ is added to

Areduce $Al X_{2} O X_{3}$ chemically to Al
Boxidise the carbon anode
Clower the melting point of the mixture and increase its electrical conductivity
Draise the operating temperature to above 2000 K

Answer: C

Pure

Al X_{2} O X_{3}

melts near 2300 K and conducts poorly. Dissolving it in molten cryolite (with

CaF X_{2}

) lowers the electrolysis temperature to about 1200 K and makes the melt conducting.

Practice p-Block Elements: Groups 13 and 14 More on Aluminium compounds and alums

Previous questionNext question

More questions on Aluminium compounds and alums

Heating hydrated aluminium chloride, AlCl3.6H2O, does not give anhydrous AlCl3 because JEE Main level
An aqueous solution of AlCl3 is acidic because JEE Main level
Which of the following is an alum? JEE Main level
When aqueous AlCl3 is mixed with aqueous Na2CO3, the observation is JEE Main level
Select the correct statement(s) about alums. JEE Main level
Potash alum, KAl(SO4)2.12H2O (9.48 g), is strongly ignited until only Al2O3 remains as the solid residue (K, S and water are lost or taken a... JEE Main level