MolSynapsequestion bank

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

NEET levelSingle correct optionDifficulty 1 of 3pb009

In the electrolytic extraction of aluminium from alumina, cryolite ( $Na X_{3} AlF X_{6}$ ) is added mainly to

Araise the melting point of alumina
Bact as the reducing agent for alumina
Clower the melting point of the mixture and increase its conductivity
Doxidise the graphite anode

Answer: C

Pure alumina melts near 2300 K and conducts poorly when molten. Cryolite (with a little fluorspar) lowers the melting point to about 1200 K and makes the melt a better conductor.

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

Previous questionNext question

More questions on Aluminium compounds and alums

Potash alum has the formula K2SO4.Al2(SO4)3.xH2O. The value of x is NEET level
Aluminium oxide is described as amphoteric because it NEET level
Aluminium vessels can be used to transport concentrated nitric acid because JEE Main level
In the vapour phase aluminium chloride exists as Al2Cl6. The number of bridging chlorine atoms and the hybridisation of each Al are JEE Main level
Which of the following is NOT an alum? JEE Main level
In the Bayer process, carbon dioxide is passed through a solution of sodium aluminate to JEE Main level