EduNinja

[Maximum number: 1]

Which statement about the extraction of metals is correct?

A

Aluminium is extracted from the ore bauxite by electrolysis.

B

Aluminium is extracted from the ore hematite by electrolysis.

C

Iron is extracted from the ore bauxite by electrolysis.

D

Iron is extracted from the ore hematite by electrolysis.

[Maximum number: 1]

Which equation represents the reduction of a compound found in hematite in the blast furnace?

A

$2 \mathrm{Al}_{2} \mathrm{O}_{3} \rightarrow 4 \mathrm{Al}+3 \mathrm{O}_{2}$

B

$\mathrm{CaO}+\mathrm{SiO}_{2} \rightarrow \mathrm{CaSiO}_{3}$

C

$2 \mathrm{FeO}+\mathrm{CO} \rightarrow \mathrm{Fe}_{2} \mathrm{O}_{3}+\mathrm{C}$

D

$\mathrm{Fe}_{2} \mathrm{O}_{3}+3 \mathrm{CO} \rightarrow 2 \mathrm{Fe}+3 \mathrm{CO}_{2}$

[Maximum number: 1]

Why is cryolite used in the extraction of aluminium by electrolysis?

A

It dissolves the aluminium oxide.

B

It protects the anodes from corrosion.

C

It changes bauxite to aluminium oxide.

D

It decreases the melting point of the aluminium.

CAIE IGCSE Chemistry 9.6 Extraction of Metals Topic Practice